RESUMEN
Using CO2 , water, and sunlight to produce solar fuel is a very attractive process, which can synchronously reduce carbon and convert solar energy into hydrocarbons. However, photocatalytic CO2 reduction is often limited by the low selectivity of reduction products and poor photocatalytic activity. In this study, S-scheme Bi5 O7 I-OVs/Cd0.5 Zn0.5 S (Bi5 O7 I-OVs/CZS-0.5) heterojunction with strong interfacial electric field (IEF) is prepared by in situ growth method. The performance of reduction CO2 to CO is studied by continuous flow photothermal catalytic (PTC) CO2 reduction platform. 12.5% Bi5 O7 I-OVs/CZS-0.5 shows excellent CO yield of 58.6 µmol g-1 h-1 and selectivity of 98.4%, which are 35.1 times than that of CZS-0.5 under visible light. The charge transfer path of the S-scheme through theoretical calculation (DFT), in situ irradiation Kelvin probe force microscope (ISI-KPFM) and in situ irradiation X-ray photoelectron spectroscopy (ISI-XPS) analysis, is verified. The study can provide useful guidance and reference for improving activity by oxygen vacancy induced strong IEF and the development of a continuous flow PTC CO2 reduction system.
RESUMEN
In this work, CE-LIF was employed to investigate the amino acid metabolites produced by Escherichia coli (E. coli) in microbial fuel cell (MFC). Two peptides, l-carnosine and l-alanyl-glycine, together with six amino acids, cystine, alanine, lysine, methionine, tyrosine, arginine were separated and detected in advance by a CE-LIF system coupled with a homemade spontaneous injection device. The injection device was devised to alleviate the effect of electrical discrimination for analytes during sample injection. All analytes could be completely separated within 8 min with detection limits of 20-300 nmol/L. Then this method was applied to analyze the substrate solution containing amino acid metabolites produced by E. coli. l-carnosine, l-alanyl-glycine, and cystine were used as the carbon, nitrogen, and sulfur source for the E. coli culture in the MFC to investigate the amino acid metabolites during metabolism. Two MFCs were used to compare the activity of metabolism of the bacteria. In the sample collected at the running time 200 h of MFC, the amino acid methionine was discovered as the metabolite with the concentrations 23.3 µg/L.
Asunto(s)
Aminoácidos/aislamiento & purificación , Fuentes de Energía Bioeléctrica , Electroforesis Capilar/métodos , Escherichia coli/química , Aminoácidos/análisis , Electroforesis Capilar/instrumentación , Concentración de Iones de Hidrógeno , Límite de DetecciónRESUMEN
Flavonoids are important active ingredients in many traditional Chinese medicines. In this paper, capillary electrophoresis with amperometric detection was employed to separate and detect eight flavonoids, rutin, quercetrin, quercetin, kaempferol, kaempferide, catechin, apigenin, and luteolin, in a home-made capillary electrophoresis device. Under the separation voltage of 2000 V, the eight flavonoids could be completely separated within 33 min in 18 mM borax running buffer at pH 10.2. Good linear relationships were obtained for all analytes and the detection limits for flavonoids ranged from 0.46 to 0.85 µM. Then, the method was applied to separate and determine the flavonoids in three traditional Chinese medicines, hippophae rhamnoides, hypericum perforatum, and cacumen platycladi. Finally, rutin, kaempferol, quercetin, and quercetrin were discovered in these medicines and the concentrations ranged from 0.28 to 9.94 mg/g. The recoveries of flavonoids ranged from 84.7 to 113%, which showed the high reliability of this method.
Asunto(s)
Medicamentos Herbarios Chinos/química , Técnicas Electroquímicas , Flavonoides/análisis , Electrodos , Electroforesis Capilar , Flavonoides/aislamiento & purificación , Medicina Tradicional ChinaRESUMEN
A high-speed separation method of capillary MEKC with LIF detection had been developed for separation and determination of amino acids in laver. The CE system comprised a manual slotted-vial array (SVA) for sample introduction that could improve the separation efficiency by reducing injection volume. Using a capillary with 80 mm effective separation length, the separation conditions for amino acids were optimized. Applied with the separation electric field strength of 300 V/cm, the ten amino acids could be completely separated within 2.5 min with 10 mol/L Na2HPO4-NaOH buffer (pH = 11.5) including 30 mmol/L SDS. Theoretical plates for amino acids ranged from 72,000 to 40,000 (corresponding to 1.1-2.0 µm plate heights) and the detection limits were between 25 and 80 nmol/L. Finally, this method was applied to analyze the composition of amino acids in laver and eight known amino acids could be found in the sample. The contents of five amino acids, tyrosine, glutamic acid, glycine, lysine, and aspartic acid that could be completely separated in real sample were determined. The recoveries ranged from 82.3% to 123% that indicated the good reliability for this method in laver sample analysis.
Asunto(s)
Aminoácidos/análisis , Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Aminoácidos/aislamiento & purificación , Tampones (Química) , Diseño de Equipo , Concentración de Iones de Hidrógeno , Límite de Detección , Algas Marinas/química , Dodecil Sulfato de Sodio/química , Factores de TiempoRESUMEN
Pheochromocytoma is a tumor of the sympathetic nervous system, characterized by atypical symptoms and signs. Pheochromocytoma metastases can be found in various tissues and organs. However, synchronous metastasis at the initial diagnosis of pheochromocytoma is rare. The present study described a case with synchronous liver metastasis at the initial diagnosis of adrenal pheochromocytoma based on imaging findings. A 41-year-old woman presented with liver pain and fatigue for 1 month. Physical examination showed increased blood pressure and heart rate with sinus tachycardia. Laboratory examination revealed normal levels of liver tumor markers and increased levels of serum or urine epinephrine and norepinephrine. CT examination revealed a large cystic solid mass in the right lobe of the liver and right adrenal gland, and the solid part of the mass was enhanced after enhancement. The pathological diagnosis was pheochromocytoma of the right adrenal gland with liver metastasis. The patient underwent right hepatectomy and right adrenal tumor resection. During the postoperative follow-up, the patient's blood pressure and catecholamine levels were within the normal range. Three years after surgery, the CT examination revealed multiple liver metastases. Chemotherapy was administered to the patient. A year later, re-examination revealed an increase and enlargement of the metastases, and the mass of the right adrenal gland remained similar to the previous one. After 6 months of follow-up, the patient succumbed to recurrence and metastasis. Preoperative diagnosis of metastatic pheochromocytoma is challenging. This case mainly emphasizes that imaging findings can help the clinical diagnosis of metastatic pheochromocytoma.
RESUMEN
As temperature serves as a versatile input signal, thermoresponsive genetic controls have gained significant interest for recombinant protein production and metabolic engineering applications. The conventional thermoresponsive systems normally require the continuous exposure of heat stimuli to trigger the prolonged expression of targeted genes, and the accompanied heat-shock response is detrimental to the bioproduction process. In this study, we present the design of thermoresponsive quorum-sensing (ThermoQS) circuits to make Escherichia coli record transient heat stimuli. By conversion of the heat input into the accumulation of quorum-sensing molecules such as acyl-homoserine lactone derived from Pseudomonas aeruginosa, sustained gene expressions were achieved by a minimal heat stimulus. Moreover, we also demonstrated that we reprogrammed the E. coli Lac operon to make it respond to heat stimuli with an impressive signal-to-noise ratio (S/N) of 15.3. Taken together, we envision that the ThermoQS systems reported in this study are expected to remarkably diminish both design and experimental expenditures for future metabolic engineering applications.
RESUMEN
Sorafenib resistance is one of the main causes of poor prognosis in patients with advanced hepatocellular carcinoma (HCC). Long noncoding RNAs (lncRNAs) function as suppressors or oncogenic factors during tumor progression and drug resistance. Here, to identify therapeutic targets for HCC, the biological mechanisms of abnormally expressed lncRNAs were examined in sorafenib-resistant HCC cells. Specifically, we established sorafenib-resistant HCC cell lines (Huh7-S and SMMC7721-S), which displayed an epithelial-mesenchymal transition (EMT) phenotype. Transcriptome sequencing (RNA-Seq) was performed to established differential lncRNA expression profiles for sorafenib-resistant cells. Through this analysis, we identified LINC00540 as significantly up-regulated in sorafenib-resistant cells and a candidate lncRNA for further mechanistic investigation. Functionally, LINC00540 knockdown promoted sorafenib sensitivity and suppressed migration, invasion, EMT and the activation of PI3K/AKT signaling pathway in sorafenib-resistant HCC cells, whereas overexpression of LINC00540 resulted in the opposite effects in parental cells. LINC00540 functions as a competing endogenous RNA (ceRNA) by competitively binding to miR-4677-3p , thereby promoting AKR1C2 expression. This is the first study that demonstrates a role for LINC00540 in enhancing sorafenib resistance, migration and invasion of HCC cells through the LINC00540/miR-4677-3p/AKR1C2 axis, suggesting that LINC00540 may represent a potential therapeutic target and prognosis biomarker for HCC.
RESUMEN
BACKGROUND: Prenatal stress (PS) can cause cognitive disorder and a range of psychological illnesses, including anxiety and depression. Icariin (ICA) has shown promising effects in improving PS-induced depressive behaviour. However, its mechanism of action remains unclear. PURPOSE: This study was performed to reveal the key targets, metabolites and gut microbiota for ICA in improving depressive behaviour in PS rat pups. METHODS: A prenatal restraint stress animal model was established for Sprague-Dawley (SD) rats in late pregnancy. Male pups were randomly divided into six groups: no stress group (NS), PS group, PS + saline group (PS_S), PS + high-dose ICA group (ICAH, 80 mg/kg*day), PS + low-dose ICA group (ICAL, 40 mg/kg*day) and PS + fluoxetine group (FLU, 10 mg/kg*day). The depressive behaviour of each group of rat pups was evaluated using open field test, forced swimming test and sucrose preference test. Different metabolites were identified using untargeted metabolomics of serum and faeces, and metabolic pathways were analyzed through MetaboAnalyst. Targets for ICA acting on depression were determined after network pharmacology was applied. An integrated network of network pharmacology and metabolomics were constructed using Cytoscape software, and molecular docking were performed to verify the interactions between ICA and key targets. Finally, gut microbiota of rat pups in each group were analyzed after 16S rDNA sequencing. RESULTS: PS could cause rat pups to exhibit depressive behaviour, and ICA could significantly improve this depressive behaviour. A total of 49 differential metabolites were found in serum and 23 differential metabolites were found in faeces, and 24 metabolites in serum and 6 metabolites in faeces could be reversed following ICA administration. Integrated analysis focused on five key targets (i.e. adenosyl homocysteinase; medium-chain specific acyl-CoA dehydrogenase, mitochondrial; thymidine phosphorylase; cGMP-specific 3',5'-cyclic phosphodiesterase and xanthine dehydrogenase/oxidase) and three metabolites (i.e. palmitoylcarnitine, methionine and hypoxanthine). Molecular docking indicated that ICA combined well with key targets. Gut microbiota analysis showed that g_Bacteroides, f_Bacteroidaceae and s_Lactobacillus reuteri were required for ICA to improve depressive behaviour. CONCLUSION: In this study, the antidepressant mechanism of ICA was clarified with a strategy of integrating metabolomics, network pharmacology and gut microbiota. ICA has a good effect on improving metabolism and increasing the abundance of probiotics in the intestine. The present research provided new insights into the anti-depressant mechanism of ICA.
Asunto(s)
Flavonoides , Microbioma Gastrointestinal , Femenino , Ratas , Masculino , Embarazo , Animales , Ratas Sprague-Dawley , Simulación del Acoplamiento Molecular , Farmacología en Red , MetabolómicaRESUMEN
Phonon-assisted upconversion photoluminescence (UCPL) plays an important role in a wide range of fields such as optical refrigeration, sensitive optical thermometry, quantum state control, and upconversion optoelectronics. High photoluminescence quantum yield (PLQY) and strong electron-phonon coupling are two basic prerequisites of efficient UCPL materials. The self-trapped exciton (STE) system with the above-mentioned advantages hints that it may be a good candidate for phonon-assisted UCPL. Here, we synthesized Rb2CuCl3 single crystals (SCs) which yield a high PLQY of the STE emission at 400 nm, and an efficient phonon-assisted UCPL was demonstrated at room temperature. By exponentially fitting the intensity of temperature-dependent UCPL spectra, we obtained an optical thermometry sensitivity of SCs up to 6 mK at 295 K. We also propose that net cooling would be possible if the PLQY is improved up to 91.5% with 345 nm excitation. Our results open a new door to explore laser cooling in STE systems.
RESUMEN
Fms-like tyrosine kinase 1 (FLT1) has been shown to regulate processes such as angiogenesis, neurogenesis, and cognitive impairment. However, the role of FLT1 in prenatal stress (PS) is unclear. The purpose of this study was to investigate the role of FLT1 in PS mothers and their offspring. Wire mesh restrainers were used to construct PS rat model. The levels of FLT1, IL-1ß, IL-6, and ROS in clinical samples and rat samples were detected by qRT-PCR, ELisa kit, and DCFH-DA fluorescence kit. Morris water maze assay and forced swimming assay were used to test the cognitive function of offspring young rats. The apoptosis level of hippocampal neurons and the expression of NMDARs were detected by MTT assay, TUNEL assay, and Western blot. The results showed that FLT1 was upregulated in PS mothers and positively correlated with PS degree. The level of FLT1 was elevated in PS model rats. Knockdown of FLT1 reduced maternal ROS and MDA levels and increased SOD levels in PS rats. Knockdown of FLT1 also reduced the secretion of IL-1ß, IL-6, and cortisol in PS rats. Inhibition of FTL1 alleviated cognitive impairment in PS offspring pups. Inhibition of FTL1 reduced hippocampal neuronal apoptosis and increased the expression of NMDARs in PS progeny. In conclusions, we demonstrated that knockdown of FLT1 inhibits maternal oxidative stress, inflammation, and cortisol secretion in PS rats. In addition, knockdown of FLT1 also alleviated cognitive dysfunction and neurodevelopmental abnormalities in PS offspring pups.
RESUMEN
Chiral optical metamaterials have attracted a great deal of attention due to their intriguing properties with respect to fundamental research and practical applications. For metamaterials with achiral structures, the system composed of metamaterials and obliquely incident light has extrinsic chirality and can produce circular dichroism (CD) effect. However, there have been few studies on the azimuth-dependent CD spectra of achiral metamaterials that have greatly improved our understanding of optical phenomena caused by external chirality. In this work, we experimentally studied the azimuth-dependent CD that originated from the extrinsic chirality of the metamaterials in an asymmetric-U shape and a U-bar-shape gold unit structure, separately. We explain the origin of the CD in the coupling of the macro-electric dipole and magnetic dipole, and the simulation results are in good agreement with the experiment. Our results provide a possible way to build an on-chip azimuth sensor based on azimuth-dependent CD spectra of metamaterials.
RESUMEN
In quasi-two-dimensional (quasi-2D) perovskite films, carriers transport in the cascade structural systems involving various quantum wells (QWs) n, but their efficiency is limited by the severe nonradiative recombination within plentiful n = 1, 2, 3 domains induced by traditional ammonium bromide passivation. Here, we fabricate the quasi-2D films with the elimination of n = 1, 2, 3 domains by introducing the ionic liquid n-butylamine acetate (BAAc) instead of n-butylamine hydrobromide (BABr), which increases the photoluminescence quantum yield (PLQY) and lowers the surface roughness of films. Due to the anion exchange between BAAc and methylamine hydrobromide (MABr), BAAc exhibits a sole passivation effect on methylamine-based perovskites. As a result, the ionic liquid-derived perovskite light-emitting diodes (PeLEDs) display blue emission at 479 nm and show significantly improved performance on external quantum efficiency (EQE) and luminance. Our finding provides insights into the passivating effect of ionic liquid on quasi-2D perovskites and will benefit fabricating PeLEDs with enhanced performance.
RESUMEN
To overcome the urgency of zirconium and hafnium separation, a novel mesoporous silica sorbent (PS-G1.0-MSNs) modified with phosphorous-functionalized G1.0 PAMAM dendrimers was prepared. The adsorption and separation behaviors of PS-G1.0-MSNs adsorbent on Zr(iv) and Hf(iv) were perfromed as a function of acidity, contact time, temperature, and ion concentrations by batch sorption methods. The maximum adsorption capacities for Zr(iv) and Hf(iv) were 25.7 mg g-1 and 5.36 mg g-1 under optimal experimental conditions, respectively, and the separation factor ß Hf/Zr = 2.0 > 1 demonstrated that the prepared sorbent had preferential selectivity for Hf(iv) in rich Zr(iv) solution. Moreover, kinetic data indicated that the sorption process on Zr(iv) and Hf(iv) achieved equilibrium within 120 min, and followed the pseudo-first-order model with a rate-determining step. The adsorption amount increased as temperature raised from 283 K to 303 K and the isothermal data plotted with the Langmuir model was better than the Freundlich model with monolayer behavior. Thermodynamic data analysis indicated that the sorption process was spontaneous and endothermic. Furthermore, XPS analysis revealed that the metal ion adsorption was mainly induced by the chemical coordination of Zr(iv) and Hf(iv) ions with N, O, P atoms of amide and phosphate groups. The present work provides good guidelines on the design of high efficient sorbent for the separation of Hf(iv) from Zr(iv) solutions.
RESUMEN
The assemblies of plasmonic nanoparticles (NPs) are the universal methods for enhancing their surface-enhanced Raman scattering (SERS) activities. However, the present methods suffer from the problems of poor reproducibility, complicated fabrication, or the adsorption of ligands on the surface, which limit their practical applications. In this work, by using a facile freeze-thaw method, we are able to fabricate the assemblies of Ag NPs with highly reproducible SERS activity without the use of ligands. Moreover, the Ag NPs can be well kept in a frozen state for a long time with few influences on the reproducibility (relative standard deviation, RSD ca. 7%), while those kept in colloid (4 °C) suffer from gradual surface oxidation and aggregation. Such a simple freeze-thaw method does not require the introduction of any ligands (or linkers) with long-term stability and reproducibility, implying its wide applications in practical SERS sensing.
Asunto(s)
Antibacterianos/análisis , Nanopartículas del Metal/química , Ofloxacino/análisis , Plata/química , Contaminantes Químicos del Agua/análisis , Explotaciones Pesqueras , Congelación , Límite de Detección , Reproducibilidad de los Resultados , Espectrometría RamanRESUMEN
BACKGROUND: Nucleolar protein 6 (NOL6) is a nucleolar RNA-associated protein that is highly conserved between species. It has been proved to be associated with the prognosis of liver cancer. However, the underlying mechanism has not been fully established. This study aimed to assess the relationship between NOL6 and liver cancer prognosis. METHODS: We constructed an NOL6-short hairpin RNA (shRNA)-expressing lentivirus. Through viral transfection, cell growth assay and fluorescence-activated cell sorting, we evaluated the effect of shRNA-mediated NOL6 knockdown on the proliferation, colony formation, and apoptosis of hepatocellular carcinoma (HCC) cells. The relationship between NOL6 expression and HCC patient survival has been established through bioinformatics analysis. We also explored the downstream molecular regulatory network of NOL6 in HCC by performing an Ingenuity Pathway Analysis in the database. RESULTS: Increased NOL6 expression was detected in HCC cells compared to normal controls; HCC patients with high NOL6 expression had poorer prognoses than those with low expression. NOL6 knockdown inhibited HCC cell proliferation, apoptosis, and colony formation. Also, MAPK8, CEBPA, and FOSL1 were selected as potential downstream genes of NOL6. CONCLUSIONS: NOL6 up-regulates HCC cell proliferation and affects downstream expression of related genes. Moreover, NOL6 is considered to be associated with poor prognosis in HCC patients.
Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Nucleares , Apoptosis/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , PronósticoRESUMEN
Smart textiles and clothing with highly controllable and tunable color changes are gaining interest because of their promising functionality. However, practical applications are still restricted by the lack of continuously processed long color-changing fibers that are suitable for industrial weaving. This work presents smart electrochromic (EC) fibers with long-range controllability and multi-environmental stability that were continuously prepared using custom-built equipment. By introducing various EC-active materials (viologens) and a unique device design (parallel dual-counter-electrode structure), multiple uniform and rapid color changes were achieved over long time ranges, including blue, magenta, green, and dull red. Furthermore, an electrochemical anticorrosive layer and outer polymer protective layer were used to enhance the electrochemical, mechanical, washing, irradiation, and thermal stabilities of the EC fibers. These fibers were knitted to form large-area, smart color-changing textiles and implanted into textiles with complex patterns to demonstrate two potential EC fiber applications in adaptive camouflage and wearable displays.
RESUMEN
The insertion of organic spacers into halide perovskite slabs has offered a trade-off between the efficiency and stability of perovskite solar cells (PSCs). The layered structure of diammonium-intercalated cesium lead halide perovskites is virtually unexplored, in contrast to several works on the monoammonium system. In this report, we find that perovskite with 1,4-butanediammonium (BDA) and cesium cations can only form n = 1 and n = 2 layered isologues defined by the chemical formula of (BDA)Csn-1Pbn(I0.7Br0.3)3n+1, while the n = 3-4 ones will self-construct into unique heterostructures comprising separated quantum wells (QWs; n = 1-2) and 3D (n = ∞) perovskites. We highlight that the 2D/3D heterostructures show a structural resemblance to that of bulk heterojunction in organics, thus improving the charge separation and transport more than surface passivation. Solar cells based on the (BDA)Cs3Pb4I9.1Br3.9 (n = 4) absorbing layer delivered a power conversion efficiency (PCE) reaching 9.49% with ideal light and thermal stability.
RESUMEN
A highly sensitive and rapid method of in-situ surface-enhanced Raman spectroscopy (SERS) combining with electrochemical preconcentration (EP) in detecting malachite green (MG) in aquaculture water was established. Ag nanoparticles (AgNPs) were synthesized and spread onto the surface of gold electrodes after centrifuging to produce SERS-active substrates. After optimizing the pH values, preconcentration potentials and times, in-situ EP-SERS detection was carried out. A sensitive and rapid analysis of the low-concentration MG was accomplished within 200s and the limit of detection was 2.4 × 10-16M.
Asunto(s)
Colorantes/análisis , Colorantes de Rosanilina/análisis , Espectrometría Raman/métodos , Contaminantes Químicos del Agua/análisis , Agua/análisis , Acuicultura , Colorantes/aislamiento & purificación , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Diseño de Equipo , Límite de Detección , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Colorantes de Rosanilina/aislamiento & purificación , Plata/química , Espectrometría Raman/instrumentación , Contaminantes Químicos del Agua/aislamiento & purificaciónRESUMEN
Leptin deficiency is principally linked to metabolic disorders. Leptin knockout (LepΔI14/ΔI14) Sprague Dawley rats created by CRISPR/Cas9 is a new model to study metabolic disorders. We used a whole rat genome oligonucleotide microarray to obtain tissue-specific gene expression profiles of the white adipose tissue, liver and hypothalamus in LepΔI14/ΔI14 and wild-type (WT) rats. We found 1,651 differentially expressed (enriched) genes in white adipose tissue, 916 in the liver, and 306 in the hypothalamus in the LepΔI14/ΔI14 rats compared to WT. Gene ontology category and KEGG pathway analysis of the relationships among differentially expressed genes showed that these genes were represented in a variety of functional categories, including fatty acid metabolism, molecular transducers and cellular processes. The reliability of the data obtained from microarray was verified by quantitative real-time PCR on 14 representative genes. These data will contribute to a greater understanding of different metabolic disorders, such as obesity and diabetes.