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The substantial increase of infections, caused by novel, sudden, and drug-resistant pathogens, poses a significant threat to human health. While numerous studies have demonstrated the antibacterial and antiviral effects of Traditional Chinese Medicine, the potential of a complex mixture of traditional Chinese Medicine with a broad-spectrum antimicrobial property remains underexplored. This study aimed to develop a complex mixture of Traditional Chinese Medicine (TCM), JY-1, and investigate its antimicrobial properties, along with its potential mechanism of action against pathogenic microorganisms. Antimicrobial activity was assessed using a zone of inhibition assay and the drop plate method. Hyphal induction of Candida albicans was conducted using RPMI1640 medium containing 10% FBS, followed by microscopic visualization. Quantitative real-time PCR (RT-qPCR) was employed to quantify the transcript levels of hyphal-specific genes such as HWP1 and ALS3. The impact of JY-1 on biofilm formation was evaluated using both the XTT reduction assay and scanning electron microscopy (SEM). Furthermore, the cell membrane integrity was assessed by protein and nucleic acid leakage assays. Our results clearly showed that JY-1 significantly inhibits the vegetative growth of Candida spp. and Cryptococcus spp. In addition, this complex mixture is effectively against a wide range of pathogenic bacteria, including Staphylococcus aureus, Vancomycin-resistant enterococci, Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae. More interestingly, JY-1 plays a direct anti-viral role against the mammalian viral pathogen vesicular stomatitis virus (VSV). Further mechanistic studies indicate that JY-1 acts to reduce the expression of hyphal specific genes HWP1 and ALS3, resulting in the suppression of the hyphal formation of C. albicans. The antimicrobial property of JY-1 could be attributed to its ability to reduce biofilm formation and disrupt the cell membrane permeability, a process resulting in microbial cell death and the release of cellular contents. Taken together, our work identified a potent broad-spectrum antimicrobial agent, a complex mixture of TCM which might be developed as a potential antimicrobial drug.
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Anti-Infecciosos , Medicina Tradicional Chinesa , Animais , Humanos , Permeabilidade da Membrana Celular , Biofilmes , Candida albicans , Anti-Infecciosos/farmacologia , Misturas Complexas/farmacologia , Permeabilidade , Testes de Sensibilidade Microbiana , MamíferosRESUMO
Dried bamboo shoots (DBS) are a natural resource with inherent silica content, which can serve as sacrificial templates for the formation of mesoporous carbon but also promote the generation of silicon carbide (SiC). Building on this, we introduced mesoporous and graphitic carbon/SiC (SiC/BSC) as the CDI electrode for copper ion (Cu2+) removal. Mesoporous carbon electrodes facilitate faster ion transport, diffusion, and electron-transfer pathways. Furthermore, SiC accelerates electron transfer and promotes faradic redox reactions during the charge and discharge processes. Consequently, the synergistic effect of SiC/BSC mesoporous carbon material leads to a promising electrode for Cu2+ capacitive deionization. Leveraging these unique properties, the SiC/BSC electrode material exhibits an outstanding CDI performance of 381.5 mg/g at 1.8 V. This study offers a strategy for the preparation of efficient mesoporous carbon materials as CDI electrodes, specifically tailored for the deionization of Cu2+ ions.
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BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is used when standard methods of standard treatment methods are not successful. Obese patients present unique challenges during ECMO due to large body size hindering sufficient flows, difficulties with patient positioning and anatomical landmark identification, and restricted radiology scans. This meta-analysis aims to investigate the impact of obesity on the outcomes of patients undergoing ECMO. METHODS: Databases (PubMed, Embase, and Scopus databases) were searched to identify relevant studies published until July 2023. Data were reported as odds ratios (OR) with 95% confidence interval (CI), and the descriptive data were reported as standard difference of means (SDM) by a random effects model. RESULTS: A literature search identified 345 studies. Of them, 18 studies met the inclusion criteria. The findings from the meta-analysis revealed no significant association between obesity and survival outcomes after ECMO (odds ratio (OR): 0.91, 95% confidence interval (CI): 0.70-1.17, p: 0.46). Moreover, no comparative significant differences were found between obese and non-obese individuals on the duration of ECMO procedure (standardized mean difference (SMD): 0.07, -0.03-0.17), length of hospital stay (-0.03, -0.19 to 0.12), and duration of ventilation support (-0.10, -0.44 to 0.24). CONCLUSION: The meta-analysis findings suggest no significant impact of obesity on the survival outcomes after the ECMO procedure. There was no significant impact of obesity on the duration of ECMO procedures, length of hospital stay, and duration of ventilation support.
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Oxigenação por Membrana Extracorpórea , Obesidade , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Obesidade/complicações , Obesidade/terapia , Tempo de Internação/estatística & dados numéricos , Resultado do TratamentoRESUMO
FERONIA (FER) is a receptor-like kinase showing versatile functions during plant growth, development, and responses to environmental stimuli. However, its functions during the interaction between fruit and necrotrophic fungal pathogens are still unclear. Combining reverse genetic approaches, physiological assays, co-immunoprecipitation, protein phosphorylation identification, and site-directed mutagenesis, we reported a tomato FER homolog SlFERL (Solanum lycopersicum FERONIA Like) involved in the immune responses to Botrytis cinerea invasion. The results indicated that SlFERL extracellular domain recognized and interacted with the secreted virulence protein BcPG1 from B. cinerea, further revealed that SlFERL triggered downstream signaling by phosphorylating SlMAP3K18 at Thr45, Ser49, Ser76, and Ser135. Moreover, we verified that SlMAP2K2 and SlMAP2K4 synergistically contributed to immune response of tomato to B. cinerea, in which SlFERL-SlMAP3K18 module substantially modulated protein level and/or kinase activity of SlMAP2K2/SlMAP2K4. These findings reveal a new pattern-triggered immune pathway, indicating that SlFERL participates in the immune responses to B. cinerea invasion via recognizing BcPG1 and fine-tuning MAPK signaling.
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Solanum lycopersicum , Botrytis/fisiologia , Frutas/metabolismo , Imunidade , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de PlantasRESUMO
We reported a controlled synthesis method to obtained carbon spheres with tunable geometry under low ZnCl2 aqueous solution conditions using polytriazine as a precursor. The polytriazine precursor was polymerized by mixing/reaction of 2,6-diaminopyridine and formaldehyde in the presence of a diluted ZnCl2 aqueous system. The obtained nanospheres were then decomposed to adulterate nitrogen porous carbon nanospheres (N-PCNSs) by the decomposition and blistering process at high temperature by degrees. ZnCl2 worked as a solid-template and played the role of a stabilizing and foaming agent in the reaction. The as-prepared N-PCNSs with controllable spherical geometry, large micro-/mesoporous volume and high nitrogen content (â¼8.5 wt %) were employed in electric double-layer capacitors that have a good specific capacitance (636 F/g at 1 A/g) and are long lasting. Besides, the N-PCNS delivered a high energy density of 22.1 Wh/Kg at a power density of 500 W/kg.
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In this work, a multi-walled carbon nanotube-modified flexible poly(styrene-butadiene) fiber membrane material was prepared for the sensitive and selective electrochemical detection of dopamine (DA) in human serum and DA injection. The flexible fiber membrane prepared by electrospinning technology is expected to realize its application in wearable devices. The obtained conductive film-based electrochemical sensor can effectively minimize interference caused by ascorbic acid and uric acid. Under the optimized experimental conditions of differential pulse voltammetry, DA gives a linear response in the range of 1-650 µM (R2 = 0.996). The detection limit of DA (signal-to noise ratio = 3) was determined to be 0.062 µM.
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Dopamina/análise , Nanotubos de Carbono/química , Ácido Ascórbico/química , Técnicas Biossensoriais/instrumentação , Butadienos/química , Técnicas Eletroquímicas , Humanos , Concentração de Íons de Hidrogênio , Poliestirenos/química , Ácido Úrico/químicaRESUMO
Efficient assimilation of alternative carbon sources in glucose-limited host niches is critical for colonization of Candida albicans, a commensal yeast that frequently causes opportunistic infection in human. C. albicans evolved mechanistically to regulate alternative carbon assimilation for the promotion of fungal growth and commensalism in mammalian hosts. However, this highly adaptive mechanism that C. albicans employs to cope with alternative carbon assimilation has yet to be clearly understood. Here we identified a novel role of C. albicans mitochondrial complex I (CI) in regulating assimilation of alternative carbon sources such as mannitol. Our data demonstrate that CI dysfunction by deleting the subunit Nuo2 decreases the level of NAD+, downregulates the NAD+-dependent mannitol dehydrogenase activity, and consequently inhibits hyphal growth and biofilm formation in conditions when the carbon source is mannitol, but not fermentative sugars like glucose. Mannitol-dependent morphogenesis is controlled by a ROS-induced signaling pathway involving Hog1 activation and Brg1 repression. In vivo studies show that nuo2Δ/Δ mutant cells are severely compromised in gastrointestinal colonization and the defect can be rescued by a glucose-rich diet. Thus, our findings unravel a mechanism by which C. albicans regulates carbon flexibility and commensalism. Alternative carbon assimilation might represent a fitness advantage for commensal fungi in successful colonization of host niches.
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Candida albicans/fisiologia , Complexo I de Transporte de Elétrons/metabolismo , Proteínas Fúngicas/metabolismo , Trato Gastrointestinal/microbiologia , Mitocôndrias/metabolismo , Animais , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Carbono/metabolismo , Complexo I de Transporte de Elétrons/genética , Feminino , Proteínas Fúngicas/genética , Trato Gastrointestinal/fisiologia , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/genética , NAD/metabolismo , SimbioseRESUMO
The transcriptional regulator Pdr1 plays a positive role in regulating azole drug resistance in Candida glabrata. Previous studies have shown the importance of the carboxyl (C)-terminal sequence of Pdr1 in fulfilling its function, as this region mediates interactions between Pdr1 and the co-activator Gal11A and is crucial for activation of Pdr1 targets. However, mechanisms of how Pdr1 is regulated, especially implication of its C-terminus in the regulatory activity, remain uncharacterized. In this study, we unexpectedly observed that the C-terminal modification of Pdr1 in an azole-resistant clinical isolate harboring a single GOF mutation, resulted in adverse effects such as decreased expression levels of Pdr1, downregulation of Pdr1 targets and azole hypersensitivity. Importantly, the C-terminal 3 × FLAG tagging significantly decreased the binding of Pdr1 to the pleiotropic drug response elements in its own promoter, promoted an irregular cellular mislocalization and thereby disrupted the transcriptional autoregulation of this master regulator. Unexpectedly, the aberrant cytoplasmic localization caused a non-functional interaction with Gal11A, a co-activator involved in drug resistance. Based on these findings, we proposed that C-terminal sequence of Pdr1 is vital for its stability and functionality, and targeting regulation of this region may represent a promising future strategy for combating C. glabrata infection and drug resistance.
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Azóis/farmacologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Farmacorresistência Fúngica , Regulação Fúngica da Expressão Gênica , Homeostase , Fatores de Transcrição/metabolismo , Análise Mutacional de DNA , Perfilação da Expressão Gênica , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Acinetobacter baumannii (AB) is critical for healthcare-associated infections (HAI) with significant regional differences in the resistance rate, but its risk factors and infection trends has not been well studied. We aimed to explore the risk factors, epidemiological characteristics and resistance of multidrug-resistant Acinetobacter baumannii (MDR-AB) in intensive care unit inpatients. METHODS: Data of patients with MDR-AB (195 cases), and with antibiotic-sensitive AB infection (294 cases, control) during January to December, 2015 in three medical centers in Xiamen, China were conducted and analyzed in the present retrospective study. RESULTS: Lower respiratory tract infection with AB accounted for 68.71%. MDR-AB was detected in 39.88% of all cases. Univariate analysis suggested that mechanical ventilation, indwelling catheter, cancer patients, length of hospitalization in intensive care unit (ICU) ≥15 d, Acute Physiology and Chronic Health Evaluation (APACHE) II score, combined using antibiotic before isolation of AB and use of third-lines cephalosporins were associated with the development of MDR-AB healthcare-associated infections. Dose-response relationship analysis suggested that the age and the days of mechanical ventilation were associated with increased infection with MDR-AB. Logistic regression analysis suggested that, mechanical ventilation, combined using antibiotic before isolation of AB, and indwelling catheter, were associated with MDR-AB infection, with odds ratios (OR) and 95% confidence intervals (CI) of 3.93 (1.52-10.14), 4.11 (1.58-10.73), and 4.15 (1.32-12.99), respectively. CONCLUSIONS: MDR-AB infection was associated with mechanical ventilation, combined using antibiotic before isolation of AB, and indwelling catheter. Furthermore, the age and the days of mechanical ventilation were associated with increased infection with MDR-AB.
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Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/microbiologia , Cefalosporinas/uso terapêutico , China/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Respiração Artificial/efeitos adversos , Estudos Retrospectivos , Fatores de RiscoRESUMO
Multi-modality image fusion provides more comprehensive and sophisticated information in modern medical diagnosis, remote sensing, video surveillance, etc. Traditional multi-scale transform (MST) based image fusion solutions have difficulties in the selection of decomposition level, and the contrast loss in fused image. At the same time, traditional sparse-representation based image fusion methods suffer the weak representation ability of fixed dictionary. In order to overcome these deficiencies of MST- and SR-based methods, this paper proposes an image fusion framework which integrates nonsubsampled contour transformation (NSCT) into sparse representation (SR). In this fusion framework, NSCT is applied to source images decomposition for obtaining corresponding low- and high-pass coefficients. It fuses low- and high-pass coefficients by using SR and Sum Modified-laplacian (SML) respectively. NSCT inversely transforms the fused coefficients to obtain the final fused image. In this framework, a principal component analysis (PCA) is implemented in dictionary training to reduce the dimension of learned dictionary and computation costs. A novel high-pass fusion rule based on SML is applied to suppress pseudo-Gibbs phenomena around singularities of fused image. Compared to three mainstream image fusion solutions, the proposed solution achieves better performance on structural similarity and detail preservation in fused images.
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Hyper-cross-linked polynaphthalene nanoparticles (PNNs) capable of catalyzing the degradation of organic pollutants upon exposure to visible light have been developed. The nascent and metal-free PNNs with a porous structure, high specific surface area, and narrow bandgap are chemically and thermally stable in the catalytic system, which make it promising as a kind of excellent photocatalytic material compared to conventional photocatalysts. The photocatalytic activity of the as-obtained PNNs exhibits remarkable photocatalytic performance for the degradation of rhodamine B (RhB) and methyl blue (MB) under the irradiation of visible light. The easy preparation, high catalytic activity, and recyclability of the PNNs open new opportunities in the visible-light-promoted degradation of organic pollutants.
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The well-known Marangoni effect perfectly supports the dynamic mechanism of organic solvent-swollen gels on water. On this basis, we report a series of energy conversion processes of concentrated droplets of polyvinylidene fluoride/dimethyl formamide (PVDF/DMF) that can transfer chemical-free energy to kinetic energy to rapidly rotate itself on water. This droplet (22.2 mg) is capable to offer kinetic energy of 0.099 µJ to propel an artificial paper rocket of 31.8 mg to move over 560 cm on water at an initial velocity of 7.9 cm s-1. As the droplet increases to 35.0 mg, a paper goldfish of 10.6 mg can be driven to swim longer at a higher initial velocity of 20 cm s-1. The kinetic energy of the droplet can be further converted to electrical energy through an electromagnetic generator, in which as a 0.5 MΩ resistor is loaded, the peak output reaches 6.5 mV that corresponds to the power density of 0.293 µW kg-1. We believe that this report would open up a promising avenue to exploit energies for applications in miniature robotics.
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In germ cells, Piwi proteins interact with a specific class of small noncoding RNAs, piwi-interacting RNAs (piRNAs). Together, these form a pathway that represses transposable elements, thus safeguarding germ cell genomes. Basic models describe the overall operation of piRNA pathways. However, the protein compositions of Piwi complexes, the critical protein-protein interactions that drive small RNA production and target recognition, and the precise molecular consequences of conserved localization to germline structures, call nuage, remains poorly understood. We purified the three murine Piwi family proteins, MILI, MIWI, and MIWI2, from mouse germ cells and characterized their interacting protein partners. Piwi proteins were found in complex with PRMT5/WDR77, an enzyme that dimethylates arginine residues. By immunoprecipitation with specific antibodies and by mass spectrometry, we found that Piwi proteins are arginine methylated at conserved positions in their N termini. These modifications are essential to direct complex formation with specific members of the Tudor protein family. Recognition of methylarginine marks by Tudor proteins can drive the localization of Piwi proteins to cytoplasmic foci in an artificial setting, supporting a role for this interaction in Piwi localization to nuage, a characteristic that correlates with proper operation of the piRNA pathway and transposon silencing in multiple organisms.
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Arginina/metabolismo , Proteínas/metabolismo , Ribonucleoproteínas/metabolismo , Testículo/metabolismo , Animais , Proteínas Argonautas , Proteínas de Ciclo Celular , Linhagem Celular , Elementos de DNA Transponíveis/fisiologia , Humanos , Masculino , Metilação , Camundongos , Proteínas Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases , Proteínas/isolamento & purificação , Proteômica , Ribonucleoproteínas Nucleares Pequenas/metabolismoRESUMO
This paper reviews the recent research and development of hyperbranched polymers (HPs) and dendrimers, and their use as templates for organic-inorganic hybrid nanomaterials. Hyperbranched polymers (HPs) are highly branched macromolecules with three-dimensional globular structures featuring unique properties such as low viscosity, high solubility, and a large number of terminal functional groups compared to their linear analogs. They are easily prepared by (1) condensation polymerization, (2) self-condensing vinyl copolymerization (SCVCP), and (3) ring-opening multibranch polymerization methods. Organic-inorganic hybrid nanomaterials are synthesized by a template approach using HPs/dendrimers. Monometallic, bimetallic (alloy and core/shell), semiconductor, and metal oxide nanoparticles have been prepared by this route. The dendrimer component of these composites serves not only as a template for preparing the nanoparticles but also as a stabilizer for the nanoparticles.
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Dendrímeros/química , Compostos Inorgânicos/química , Impressão Molecular/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Compostos Orgânicos/química , Polímeros/química , Substâncias Macromoleculares/química , Conformação Molecular , Propriedades de SuperfícieRESUMO
Owing to its versatile roles in almost all aspects of plants, FERONIA (FER), a receptor-like kinase of the Catharanthus roseus receptor-like kinase 1-like (CrRLK1L) subfamily, has received extensive research interests during the past decades. Accumulating evidence has been emerged that FER homologs in horticultural crops also play crucial roles in reproductive biology and responses to environmental stimuli (abiotic and biotic stress factors). Here, we provide a review for the latest advances in the studies on FER homologs in modulating stress responses in horticultural crops, and further analyze the underlying mechanisms maintained by FER. Moreover, we also envisage the missing links in current work and provide a perspective for future studies on this star protein.
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Background: With the worsening of the greenhouse effect, the correlation between the damp-heat environment (DH) and the incidence of various diseases has gained increasing attention. Previous studies have demonstrated that DH can lead to intestinal disorders, enteritis, and an up-regulation of NOD-like receptor protein 3 (NLRP3). However, the mechanism of NLRP3 in this process remains unclear. Methods: We established a DH animal model to observe the impact of a high temperature and humidity environment on the mice. We sequenced the 16S rRNA of mouse feces, and the RNA transcriptome of intestinal tissue, as well as the levels of cytokines including interferon (IFN)-γ and interleukin (IL)-4 in serum. Results: Our results indicate that the intestinal macrophage infiltration and the expression of inflammatory genes were increased in mice challenged with DH for 14 days, while the M2 macrophages were decreased in Nlrp3 -/- mice. The alpha diversity of intestinal bacteria in Nlrp3 -/- mice was significantly higher than that in control mice, including an up-regulation of the Firmicutes/Bacteroidetes ratio. Transcriptomic analysis revealed 307 differentially expressed genes were decreased in Nlrp3 -/- mice compared with control mice, which was related to humoral immune response, complement activation, phagocytic recognition, malaria and inflammatory bowel disease. The ratio of IFN-γ/IL-4 was decreased in control mice but increased in Nlrp3 -/- mice. Conclusions: Our study found that the inflammation induced by DH promotes Th2-mediated immunity via NLRP3, which is closely related to the disruption of intestinal flora.
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Microbioma Gastrointestinal , Temperatura Alta , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células Th2 , Animais , Camundongos , Alarminas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Microbioma Gastrointestinal/imunologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Células Th2/imunologiaRESUMO
AIMS: To evaluate the visual function and foveal architecture in patients with stage 3 idiopathic epiretinal membrane (iERM). METHODS: A cross-sectional observational study included 56 eyes of 52 patients with stage 3 iERM. The patients were classified into type A ectopic inner foveal layers (EIFL) and type B EIFL based on the presence of a continuous hyporeflective band. Visual function and foveal microarchitecture were assessed in enrolled eyes. Best-corrected visual acuity (BCVA), metamorphopsia scores, retinal sensitivity and optical coherence tomography (OCT)/OCT angiography features were compared between two subtypes. RESULT: The BCVA in type A EIFL and type B EIFL was 0.22 logarithm of minimal angle of resolution (logMAR) (0.15 logMAR, 0.40 logMAR) and 0.53±0.23 logMAR, respectively (p=0.002). Type B EIFL had higher average metamorphopsia scores, especially horizontal metamorphopsia scores, than type A (p=0.013, p=0.007, respectively). Type B EIFL had worse central 2° foveal sensitivity than type A (p=0.034). Type B EIFL had thicker central foveal thickness and EIFL thickness (514.08±73.80 µm vs 444.41±56.57 µm, p=0.001; 159.75±78.30 µm vs 48.44±18.37 µm, p<0.0001; respectively). The foveal avascular zone area of type B EIFL was smaller than that of type A (0.042±0.022 mm2 vs 0.077±0.039 mm2, p<0.0001). The vessel density and flow area of the superficial vascular complex in type B EIFL were larger than those in type A (both p=0.001). CONCLUSIONS: Type B EIFL demonstrated significantly worse visual function than type A EIFL, along with marked differences in foveal microstructure and microvasculature. Our study complements the current staging of iERM and helps determine the optimal timing of iERM surgery.
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An easy template-free approach to the fabrication of pure carbon microspheres has been achieved via direct pyrolysis of as-prepared polyaromatic hydrocarbons including polynaphthalene and polypyrene. The polyaromatics were synthesized from aromatic hydrocarbons (AHCs) using anhydrous zinc chloride as the Friedel-Crafts catalyst and chloromethyl methyl ether as a cross-linker. The experimental results show that the methylene bridges between phenyl rings generate a hierarchical porous polyaromatic precursor to form three-dimensionally (3D) interconnected micro-, meso-, and macroporous networks during carbonization. These hierarchical porous carbon aggregates of spherical carbon spheres exhibit faster ion transport/diffusion behavior and increased surface area usage in electric double-layer capacitors. Furthermore, micropores are present in the 3D interconnected network inside the cross-linked AHC-based carbon microspheres, thus imparting an exceptionally large, electrochemically accessible surface area for charge accumulation.
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Carbono/química , Microesferas , Hidrocarbonetos Policíclicos Aromáticos/química , Técnicas Eletroquímicas , Estrutura Molecular , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Propriedades de SuperfícieRESUMO
Tetraarylmethane compounds consisting of two pyrogallol and two aniline units, namely, Ar2CAr'2 {Ar = 3,4,5-C6H2(OH)3 and Ar' = 3,5-R2-4-C6H2NH2 [R = Me (1), iPr (2)]} exhibit excellent self-assembly behavior. Compound 1 yields size-tunable hollow nanospheres (HNSs) with a narrow size distribution, and 2 yields various morphologies ranging from microtubules to microrods via self-assembly induced by hydrogen bonding and π-π stacking interactions. On the basis of the experimental results, a plausible mechanism for morphology tunability was proposed. As a means of utilizing the self-assembled HNSs for targeting controlled drug delivery, folic acid (FA) and rhodamine 6G (Rh6G) were grafted onto compound 1 to yield the FA-Rh6G-1 complex. The HNSs fabricated with FA-Rh6G-1 showed low cytotoxicity against human embryonic kidney 293T cells and CT26 colon carcinoma cells and good doxorubicin (DOX) loading capacity (9.6 wt %). The FA receptor-mediated endocytosis of FA-Rh6G-1 HNSs examined by using a confocal laser scanning microscope and a flow cytometer revealed that the uptake of FA-Rh6G-1 HNSs into CT26 cells was induced by FA receptor-mediated endocytosis. In vitro drug delivery tests showed that the DOX molecules were released from the resulting HNSs in a sustainable and pH-dependent manner, demonstrating a potential application for HNSs in targeted drug delivery for cancer therapy.
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Portadores de Fármacos/química , Linhagem Celular , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/efeitos adversos , Ácido Fólico/química , Humanos , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Nanosferas/química , Rodaminas/químicaRESUMO
Acetonitrile wastewater is difficult to treat due to its high salinity and toxicity to microorganisms. In this paper, a micro electro-activated carbon fiber coupled system (ME-ACF) was established to treat simulated acetonitrile wastewater. In the 200 ml system, the concentration of acetonitrile adsorbed by ACF was 91.3 mg/L, while that of acetonitrile adsorbed by ME-ACF was 150.6 mg/L, and the removal efficiency was increased by 65 % in comparison. The activated carbon fibers before and after the reaction were subjected to a series of characterization, and it was found that the SABET decreased from 1393.48 m2/g to 1114.93 m2/g and 900.23 m2/g, respectively, but the oxygen on the surface of the activated carbon fibers was increased, and the effect of the micro electrolytic system on the activated carbon fibers was then analyzed. The possible reasons for the formation of acetic acid contained in the products were also discussed using DFT simulations. The removal mechanism of acetonitrile by ME-ACF was considered to be electrically enhanced adsorption and electro-catalytic hydrolysis.