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Developing transparent conductors to replace indium tin oxide (ITO) is a critical objective in the field of organic optoelectronics. Non-atomically doped (NAD) ZnO thin films, while currently exhibiting limited conductivity, are highly promising candidates due to their unique advantages, such as having complete transparency in both the visible and near-infrared spectral regions, solution processability, and the desired surface electronic properties. In this work, the impact of surface modification by insulating polymers on the ultraviolet-enhanced conductivity of NAD-ZnO films is investigated. It was found that polymer modifiers that are rich in amino and hydroxyl groups are effective at increasing the concentration of oxygen vacancies and the conductivity of NAD-ZnO films. The highest conductivity of over 1000 S cm-1, which is more than twice as high as the previous record for NAD-ZnO films, is achieved using polyethylenimine ethoxylated (PEIE) to modify NAD-ZnO films. Subsequently, the replacement of ITO in organic photovoltaic devices by a ZnO/PEIE electrode is realized. The ZnO/PEIE-based OPV devices that were created exhibit performances comparable to those of ITO-based devices under simulated solar illumination and performances better than those achieved with ITO-based devices under simulated indoor illumination. These results make NAD-ZnO a promising candidate for the widespread replacement of ITO in optoelectronic devices.
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The high morbidity of patients with coronavirus disease 2019 (COVID-19) brings on a panic around the world. COVID-19 is associated with sex bias, immune system, and preexisting chronic diseases. We analyzed the gene expression in patients with COVID-19 and in their microbiota in order to identify potential biomarkers to aid in disease management. A total of 129 RNA samples from nasopharyngeal, oropharyngeal, and anal swabs were collected and sequenced in a high-throughput manner. Several microbial strains differed in abundance between patients with mild or severe COVID-19. Microbial genera were more abundant in oropharyngeal swabs than in nasopharyngeal or anal swabs. Oropharyngeal swabs allowed more sensitive detection of the causative SARS-CoV-2. Microbial and human transcriptomes in swabs from patients with mild disease showed enrichment of genes involved in amino acid metabolism, or protein modification via small protein removal, and antibacterial defense responses, respectively, whereas swabs from patients with severe disease showed enrichment of genes involved in drug metabolism, or negative regulation of apoptosis execution, spermatogenesis, and immune system, respectively. Microbial abundance and diversity did not differ significantly between males and females. The expression of several host genes on the X chromosome correlated negatively with disease severity. In this way, our analyses identify host genes whose differential expression could aid in the diagnosis of COVID-19 and prediction of its severity via non-invasive assay.
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Six new aromatic acids (1-6) and three new leucine derivatives containing an unusual oxime moiety (7-9) were isolated and identified from the deep-sea-derived actinomycetes strain Streptomyces chumphonensis SCSIO15079, together with two known compounds (10-11). The structures of 1-9 including absolute configurations were determined by detailed NMR, MS, and experimental and calculated electronic circular dichroism spectroscopic analyses. Compounds 1-9 were evaluated for their antimicrobial and cytotoxicity activities, as well as their effects on intracellular lipid accumulation in HepG2 cells. Compounds 3 and 4, with the most potent inhibitory activity on intracellular lipid accumulation at 10 µM, were revealed with potential antihyperlipidemic effects, although the mechanism needs to be further studied.
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Actinobacteria , Actinomyces , Dicroismo Circular , Hipolipemiantes/farmacología , Leucina , Lípidos , Estructura MolecularRESUMEN
The mangrove-sediment-derived actinomycete strain Streptomyces psammoticus SCSIO NS126 was found to have productive piericidin metabolites featuring anti-renal cell carcinoma activities. In this study, in order to explore more diverse piericidin derivatives, and therefore to discover superior anti-tumor lead compounds, the NS126 strain was further fermented at a 300-L scale under optimized fermentation conditions. As a result, eight new minor piericidin derivatives (piericidins L-R (1-7) and 11-demethyl-glucopiericidin A (8)) were obtained, along with glucopiericidin B (9). The new structures including absolute configurations were determined by spectroscopic methods coupled with experimental and calculated electronic circular dichroism. We also proposed plausible biosynthetic pathways for these unusual post-modified piericidins. Compounds 1 and 6 showed selective cytotoxic activities against OS-RC-2 cells, and 2-5 exhibited potent cytotoxicity against HL-60 cells, with IC50 values lower than 0.1 µM. The new piericidin glycoside 8 was cytotoxic against ACHN, HL-60 and K562, with IC50 values of 2.3, 1.3 and 5.5 µM, respectively. The ability to arrest the cell cycle and cell apoptosis effects induced by 1 and 6 in OS-RC-2 cells, 2 in HL-60 cells, and 8 in ACHN cells were then further investigated. This study enriched the structural diversity of piericidin derivatives and confirmed that piericidins deserve further investigations as promising anti-tumor agents.
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Aminoglicósidos/farmacología , Antineoplásicos/farmacología , Organismos Acuáticos/química , Streptomyces/química , Aminoglicósidos/química , Animales , Antineoplásicos/química , Línea Celular Tumoral/efectos de los fármacos , HumanosRESUMEN
A series of novel pyrazolo[3,4-d]pyrimidin-4-one derivatives were synthesized and evaluated for their anti-phosphodiesterase-5 (PDE-5) activity. A total of 28 compounds, containing alkyl and aryl groups at the 1-N and 3-C positions on the pyrazole ring, and also bearing different alkyl substituents on the piperazine ring were synthesized. Four compounds (4d, 5d, 6d, and 5o) were found to have better inhibitory activity against PDE-5 (IC50 < 10 nM). All four of the most active compounds contain a phenyl ring at the N1 position. Compounds containing a 3,5-dimethylpiperazinyl group show better activity than others. These results suggest that compound 5o can be used as a lead structure for developing new inhibitors of PDE-5.
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Inhibidores de Fosfodiesterasa 5/farmacología , Pirazoles/farmacología , Pirimidinas/farmacología , Citrato de Sildenafil/farmacología , Concentración 50 Inhibidora , Inhibidores de Fosfodiesterasa 5/síntesis química , Inhibidores de Fosfodiesterasa 5/química , Pirazoles/síntesis química , Pirazoles/química , Pirimidinas/síntesis química , Pirimidinas/química , Citrato de Sildenafil/química , Relación Estructura-ActividadRESUMEN
A ZnCl2-promoted synthesis of 1,3-benzoxazin-4-one from 2-hydroxybenzonitriles and ketones was developed. This method displays facile access to a diverse range of substituted 1,3-benzoxazin-4-ones in good yields. This synthetic protocol has advantages: (i) easy availability of starting material; (ii) strong corrosive acid-free condition; (iii) high yield.
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BACKGROUND: Accumulating evidence has linked environmental exposure, such as ambient air pollution and meteorological factors, to the development and severity of cardiovascular diseases (CVDs), resulting in increased healthcare demand. Effective prediction of demand for healthcare services, particularly those associated with peak events of CVDs, can be useful in optimizing the allocation of medical resources. However, few studies have attempted to adopt machine learning approaches with excellent predictive abilities to forecast the healthcare demand for CVDs. This study aims to develop and compare several machine learning models in predicting the peak demand days of CVDs admissions using the hospital admissions data, air quality data and meteorological data in Chengdu, China from 2015 to 2017. METHODS: Six machine learning algorithms, including logistic regression (LR), support vector machine (SVM), artificial neural network (ANN), random forest (RF), extreme gradient boosting (XGBoost), and light gradient boosting machine (LightGBM) were applied to build the predictive models with a unique feature set. The area under a receiver operating characteristic curve (AUC), logarithmic loss function, accuracy, sensitivity, specificity, precision, and F1 score were used to evaluate the predictive performances of the six models. RESULTS: The LightGBM model exhibited the highest AUC (0.940, 95% CI: 0.900-0.980), which was significantly higher than that of LR (0.842, 95% CI: 0.783-0.901), SVM (0.834, 95% CI: 0.774-0.894) and ANN (0.890, 95% CI: 0.836-0.944), but did not differ significantly from that of RF (0.926, 95% CI: 0.879-0.974) and XGBoost (0.930, 95% CI: 0.878-0.982). In addition, the LightGBM has the optimal logarithmic loss function (0.218), accuracy (91.3%), specificity (94.1%), precision (0.695), and F1 score (0.725). Feature importance identification indicated that the contribution rate of meteorological conditions and air pollutants for the prediction was 32 and 43%, respectively. CONCLUSION: This study suggests that ensemble learning models, especially the LightGBM model, can be used to effectively predict the peak events of CVDs admissions, and therefore could be a very useful decision-making tool for medical resource management.
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Hospitalización , Aprendizaje Automático , China , Exposición a Riesgos Ambientales , Humanos , Modelos Logísticos , Máquina de Vectores de SoporteRESUMEN
Cytochalasans have continuously aroused considerable attention among the chemistry and pharmacology communities due to their structural complexities and pharmacological significances. Sixteen structurally diverse chaetoglobosins, 10-(indol-3-yl)-[13]cytochalasans, including a new one, 6-O-methyl-chaetoglobosin Q (1), were isolated from the coral-associated fungus Chaetomium globosum C2F17. Their structures were accomplished by extensive spectroscopic analysis combined with single-crystal X-ray crystallography and ECD calculations. Meanwhile, the structures and absolute configurations of the previously reported compounds 6, 12, and 13 were confirmed by single-crystal X-ray analysis for the first time. Chaetoglobosins E (6) and Fex (11) showed significant cytotoxicity against a panel of cancer cell lines, K562, A549, Huh7, H1975, MCF-7, U937, BGC823, HL60, Hela, and MOLT-4, with the IC50 values ranging from 1.4 µM to 9.2 µM.
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Antozoos/microbiología , Chaetomium/química , Alcaloides Indólicos/aislamiento & purificación , Animales , Antozoos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacología , Neoplasias/tratamiento farmacológicoRESUMEN
The urban environment is a complex ecosystem influenced by strong human disturbances in multi-environmental media, so it is necessary to analyze urban environmental pollutants through the comprehensive analysis of different media. Soil, road dust, foliar dust, and camphor leaves from 32 sample sites in Shanghai were collected for the analysis of mercury contamination in soil-road dust-leaves-foliar dust systems. Mercury concentrations in surface soils in Shanghai were the highest, followed by road dust, foliar dust, and leaves, successively. The spatial distribution of mercury in the four environmental media presented different distribution patterns. Except for the significant correlation between mercury concentrations in road dust and mercury concentrations in leaves (r = 0.56, p < 0.001), there was no significant correlation between the other groups in the four media. Besides this, there was no significant correlation between mercury concentrations and land types. The LUR (Land use regression) model was used to assess the impact of urbanization factors on mercury distribution in the environment. The results showed that soil mercury was affected by factories and residential areas. Foliar dust mercury was affected by road density and power plants. Leaf mercury was affected by power plants and road dust mercury was affected by public service areas. The highest average HI (Hazard index) value of mercury in Shanghai was found in road dust, followed by surface soil and foliar dust. The HI values for children were much higher than those for adults. However, the HI values of mercury exposure in all sampling sites were less than one, suggesting a lower health risk level. The microscopic mechanism of mercury in different environmental media was suggested to be studied further in order to learn the quantitative effects of urbanization factors on mercury concentrations.
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Polvo/análisis , Mercurio/análisis , Contaminantes del Suelo/análisis , Adulto , Niño , China , Monitoreo del Ambiente , Humanos , Centrales Eléctricas , Medición de RiesgoRESUMEN
A growing body of evidence indicates that glycosylated natural products have become vital platforms for the development of many existing first-line drugs. This review covers 205 new glycosides over the last 22 years (1997-2018), from marine microbes, including bacteria, cyanobacteria, and fungi. Herein, we discuss the structures and biological activities of these compounds, as well as the details of their source organisms.
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The Zinc finger domains (ZnFs), which contain finger-like protrusions stabilized by zinc ions and function to bind DNA, RNA, protein and lipid substrates, are ubiquitously present in a large number of proteins. In this study, a novel protein containing a single C4 type Znf domain (SZnf) was identified from Pacific white shrimp, Litopenaeus vannamei and its role in immunity was further investigated. The ZnF domain of SZnF but not other regions shared high homology with those of fushi tarazu-factor 1 (FTZ-F1) proteins. The SZnF protein was mainly localized in the cytoplasm and was also present in the nucleus at a small level. SZnF was high expressed in the scape and muscle tissues of healthy shrimp and its expression in gill and heptopancreas was strongly up-regulated during bacterial infection. Silencing of SZnf in vivo could strongly increase the susceptibility of shrimp to infection with Vibrio parahaemolyticus but not white spot syndrome virus (WSSV), suggesting that SZnf could be mainly involved in antibacterial responses. Both dual luciferase reporter assays and real-time PCR analysis demonstrated that SZnf could positively regulate the expression of various antimicrobial peptides in vitro and in vivo, which could be part of the mechanism underlying its antibacterial effects. In summary, the current study could help learn more about the function of ZnF-containing proteins and the regulatory mechanisms of immune responses against pathogen infection in crustaceans.
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Proteínas de Artrópodos , Penaeidae , Dedos de Zinc , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Branquias/microbiología , Músculos/microbiología , Penaeidae/genética , Penaeidae/inmunología , Penaeidae/microbiología , Interferencia de ARN , Vibrio parahaemolyticus , Virus del Síndrome de la Mancha Blanca 1 , Dedos de Zinc/genética , Dedos de Zinc/inmunologíaRESUMEN
Total phosphorus is one of the key water quality parameters in environmental monitoring. To precisely determine the total phosphorus, water samples have to be pretreated to convert the various forms of phosphorus to orthophosphate. Conventionally, pretreatment is accomplished by heating, acidification, and oxidation in a digestion equipment, which is dangerous, time-consuming, and complicated. Herein, we propose a novel high-performance electrochemical oxidation protocol for phosphorus digestion based on a PbO2 electrode. The electrode, which has a hydrophobic and stable surface, was prepared by electrochemical deposition on a titanium substrate and has high hydroxyl radical utilization when digesting total phosphorus. As a result, 90% of sodium glycerophosphate was digested within 30 minutes, and high digestion ratios of acephate, glyphosate, and inland water samples were obtained as well. In addition, this electrochemical digestion protocol does not required heating and acidification steps, which shortens the digestion time. Therefore, a rapid quantification of total phosphorus in the water sample was achieved.
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In the evolutionarily conserved canonical NF-κB pathway, degradation of the NF-κB inhibitor IκB in the cytoplasmic NF-κB/IκB complex allows the liberated NF-κB to translocate into the nucleus to activate various target genes. The regulatory mechanism governing this process needs further investigation. In this study, a novel microRNA, temporarily named miR-1959, was first identified from an invertebrate Litopenaeus vannamei miR-1959 targets the 3'-untranslated region of the IκB homolog Cactus gene and reduces the protein level of Cactus in vivo, whereas the NF-κB homolog Dorsal directly binds the miR-1959 promoter to activate its transcription. Therefore, miR-1959 mediates a positive feedback regulatory loop, in that Dorsal activates miR-1959 expression, and in turn, miR-1959 inhibits the expression of Cactus, further leading to enhanced activation of Dorsal. Moreover, miR-1959 regulates the expression of many antimicrobial peptides in vivo and is involved in antibacterial immunity. To our knowledge, it is the first discovery of a microRNA-mediated feedback loop that directly regulates the NF-κB/IκB complex. This positive feedback loop could collaborate with the known NF-κB/IκB negative loop to generate a dynamic balance to regulate the activity of NF-κB, thus constituting an effective regulatory mechanism at the critical node of the NF-κB pathway.
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Núcleo Celular/metabolismo , Quinasa I-kappa B/genética , MicroARNs/genética , FN-kappa B/metabolismo , Penaeidae/inmunología , Regiones no Traducidas 3'/genética , Animales , Péptidos Catiónicos Antimicrobianos/genética , Evolución Biológica , Clonación Molecular , Retroalimentación Fisiológica , Inmunidad Innata/genética , FN-kappa B/genética , Regiones Promotoras Genéticas/genética , Transporte de Proteínas , Transducción de SeñalRESUMEN
The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway was known to participate in dozens of immune responses in organisms. Domeless, first identified in Drosophila melanogaster, is a unique receptor involved in invertebrate JAK/STAT pathway. In this study, a cytokine receptor (LvDOME) was identified in Litopenaeus vannamei. The LvDOME cDNA was 5178bp in length with an Open Reading Frame (ORF) of 4191bp. LvDOME contained two cytokine binding modules (CBMs) and three fibronectin-type-III-like (FNIII) domains, similar to most vertebrate IL-6 receptors. LvDOME was expressed highest in shrimp muscle and could be up-regulated in the late stage of white spot syndrome virus (WSSV) infection. LvDOME could significantly enhance the activity of the WSSV wsv069 gene promoter through acting on the STAT-binding motif, suggesting LvDOME could activate the JAK/STAT pathway. Moreover, knockdown of LvDOME resulted in lower cumulative mortality of shrimps and less WSSV copies, suggesting LvDOME may be hijacked by WSSV to benefit virus replication. To our knowledge, this is the first report on the receptor of JAK/STAT pathway in shrimp.
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Proteínas de Artrópodos/genética , Penaeidae/genética , Penaeidae/inmunología , Receptores de Citocinas/genética , Transducción de Señal , Virus del Síndrome de la Mancha Blanca 1/fisiología , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/química , Proteínas de Artrópodos/metabolismo , Regulación de la Expresión Génica , Datos de Secuencia Molecular , Penaeidae/metabolismo , Filogenia , Receptores de Citocinas/química , Receptores de Citocinas/metabolismoRESUMEN
Hemolin is a specific immune protein belonging to immunoglobulin superfamily and firstly identified in insects. Growing evidences suggest that Hemolin can be activated by bacterial and viral infections and may play an important role in antimicrobial immunity. In this paper, we firstly identified a Hemolin-like protein from Litopenaeus vannamei (LvHemolin). Sequence analysis showed that LvHemolin shares high similarity with insect Hemolins and is mainly composed of seven immunoglobulin (Ig) domains which form a 'horseshoe' tertiary structure. Tissue distribution analysis demonstrated that LvHemolin mainly expressed in stomach, gill, epithelium and pyloric cecum of L. vannamei. After challenge with pathogens or stimulants, expression of LvHemolin was significantly up-regulated in both gill and stomach. Agglutination analysis demonstrated that recombinant LvHemolin protein purified from Escherichia coli could accelerate the agglutination of Vibrio parahaemolyticus, E. coli, Staphylococcus aureus, and Bacillus subtilis in the presence of Ca(2+). To verify the immune function of LvHemolin in vivo, shrimps were injected with gene-specific dsRNA, followed by challenge with white spot syndrome virus (WSSV) or V. parahaemolyticus. The results revealed that silence of LvHemolin could increase the cumulative mortalities of shrimps challenged by pathogens and increase the WSSV copies in shrimp tissues. These suggested that Hemolin could play an important role in shrimp innate immune defense against bacterial and viral infections.