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BACKGROUND: Hepatocellular carcinoma (HCC) has a high incidence and mortality worldwide, which seriously threatens people's physical and mental health. Coagulation is closely related to the occurrence and development of HCC. Whether coagulation-related genes (CRGs) can be used as prognostic markers for HCC remains to be investigated. METHODS: Firstly, we identified differentially expressed coagulation-related genes of HCC and control samples in the datasets GSE54236, GSE102079, TCGA-LIHC, and Genecards database. Then, univariate Cox regression analysis, LASSO regression analysis, and multivariate Cox regression analysis were used to determine the key CRGs and establish the coagulation-related risk score (CRRS) prognostic model in the TCGA-LIHC dataset. The predictive capability of the CRRS model was evaluated by Kaplan-Meier survival analysis and ROC analysis. External validation was performed in the ICGC-LIRI-JP dataset. Besides, combining risk score and age, gender, grade, and stage, a nomogram was constructed to quantify the survival probability. We further analyzed the correlation between risk score and functional enrichment, pathway, and tumor immune microenvironment. RESULTS: We identified 5 key CRGs (FLVCR1, CENPE, LCAT, CYP2C9, and NQO1) and constructed the CRRS prognostic model. The overall survival (OS) of the high-risk group was shorter than that of the low-risk group. The AUC values for 1 -, 3 -, and 5-year OS in the TCGA dataset were 0.769, 0.691, and 0.674, respectively. The Cox analysis showed that CRRS was an independent prognostic factor for HCC. A nomogram established with risk score, age, gender, grade, and stage, has a better prognostic value for HCC patients. In the high-risk group, CD4+T cells memory resting, NK cells activated, and B cells naive were significantly lower. The expression levels of immune checkpoint genes in the high-risk group were generally higher than that in the low-risk group. CONCLUSIONS: The CRRS model has reliable predictive value for the prognosis of HCC patients.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Pronóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Nomogramas , Factores de Riesgo , Microambiente TumoralRESUMEN
Ionic liquid (IL)-modified UiO-66-NH2 composite was prepared and used as sorbent of dispersed solid-phase extraction (dSPE) for extracting trace benzoylurea insecticides (BUs) from complex environmental matrices. The IL in framework endowed the prepared material had electropositive characteristics, which can produce interaction with electron rich guest molecules, such as BUs. The high thermal and chemical stability of UiO-66-NH2/IL enabled it to be reused for 16 times without significant reduction in adsorption performance. Due to the multiple forces including π-π, hydrogen bonding, and fluorine-fluorine interaction, UiO-66-NH2/IL showed good adsorption performance, short adsorption time (20 s) and rapid desorption ability (60 s) for BUs. Under the optimal conditions, the method exhibited wide linear range (0.02-500 ng mL-1) with correlation coefficient (R2) not worse than 0.9928, high enrichment factor (252-300), and low detection limit (0.005-0.4 ng mL-1). The dispersed solid phase extraction coupling with high-performance liquid chromatography-diode array detector (dSPE-HPLC-DAD) was successfully used to detection of BUs in real environmental samples and satisfactory recoveries were obtained (80.5%±2.4-118%±3.2). The results indicated that UiO-66-NH2/IL composite can be a potential sorbent for the preconcentration of trace insecticides in environmental samples.
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Using MIL-101(Fe) as the source of carbon and Fe, a magnetic porous carbon (MPC) material with Fe3C nanoparticles encapsulated in porous carbon was prepared through one-pot pyrolysis under N2 atmosphere. With MPC as adsorption material, a stir bar sorptive-dispersive microextraction (SBSDME) method was proposed to extract and preconcentrate sulfonamides (SAs) prior to HPLC-DAD determination. To investigate their extraction ability, different MPC materials were prepared under different carbonization temperatures (600, 700, 800, 900, and 1000 °C). The material prepared under 900 °C (MPC-900) exhibited the highest extraction ability for SAs. The as-prepared MPC materials were also characterized by Raman spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, zeta potential, and other techniques. The main parameters that affect extraction were systematically studied. Under optimal conditions, favorable linearity (R2 ≥ 0.9938) and detection limits (0.02-0.04 ng mL-1) of sulfonamides were obtained. The average recoveries for spiked milk and lake water samples ranged from 76.9 to 109% and from 75.4 to 118% with RSDs of 3.10-9.63% and 1.71-11.3%, respectively. Sulfameter and sulfisoxazole were detected in milk sample. Sulfisoxazole was detected in the lake water sample. The MPC-900 material demonstrated excellent reusability. It can be reused 24 times with peak areas having no obvious decline. The method can be applied to extract ultra-trace compounds in complex sample matrices. Schematic presentation of a stir bar sorptive-dispersive microextraction (SBSDME) by using magnetic porous carbon (MPC) composites as sorbent combined with high-performance liquid chromatography for sensitive analysis of sulfonamides in milk and lake water samples.
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In this study, transport behaviors of graphene oxide (GO) in saturated uncoated (i.e., clean sand) and goethite-coated sand porous media were examined as a function of the phosphate. We found that phosphate enhanced the transport of GO over a wide range of solution chemistry (i.e., pH 5.0-9.0 and the presence of 10 mmol/L Na+ or 0.5 mmol/L Ca2+). The results were mainly ascribed to the increase of electrostatic repulsion between nanoparticles and porous media. Meanwhile, deposition site competition induced by the retained phosphate was another important mechanism leading to promote GO transport. Interestingly, when the phosphate concentration increased from 0.1 to 1.0 mmol/L, the transport-enhancement effect of phosphate in goethite-coated sand was to a much larger extent than that in clean sand. The observations were primarily related to the difference in the total mass of retained phosphate between the iron oxide-coated sand and clean sand columns, which resulted in different degrees of the electrostatic repulsion and competitive effect of phosphate. When the background solution contained 0.5 mmol/L Ca2+, phosphate could be bind to sand/ goethite-coated sand surface by cation bridging; and consequently, promoted competition between phosphate and nanoparticles for deposition sites, which was an important mechanism for the enhanced effect of phosphate. Moreover, the DLVO theory was applicable to describe GO transport behaviors in porous media in the absence or presence of phosphate. Taken together, these findings highlight the important status and role of phosphate on the transport and fate of colloidal graphene oxide in the subsurface environment.
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Nanopartículas , Dióxido de Silicio , Compuestos Férricos , Grafito , Fosfatos , Porosidad , ArenaRESUMEN
The monodispersed mesoporous SiO2@metal-organic framework (MSN@MIL-101(Fe)) composites were prepared by grafting MSN-NH2 onto MIL-101(Fe) particles with a solvothermal method. The adsorption ability of the composites was greatly improved compared to that of pristine MSNs or MIL-101(Fe) for phytohormones (Phys). The MSN@MIL-101(Fe) composites were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive spectrometer, and mapping analysis. Using MSN@MIL-101(Fe) composites as sorbent, a dispersive solid-phase extraction procedure (dSPE) was developed to extract three endogenous Phys (abscisic acid (ABA), indole-3-aceticacid (IAA), and indole-3-butyric acid (IBA)) and two exogenous Phys (1-naphthylacetic acid (1-NAA) and 2-naphthylacetic acid (2-NAA)) prior to HPLC-DAD analysis. The experimental parameters including sample volume, sorbent amount, adsorption time, adsorption pH, desorption time, and desorption solvent on extraction efficiency were optimized and evaluated. Under optimized conditions, the working range of 0.08 to 0.45 ng mL-1 with enrichment factors from 144 to 207 were achieved. The linear range is 0.75-200 ng mL-1 for IAA, 0.20-200 ng mL-1 for ABA, and 1.0-200 ng mL-1 for IBA, 1-NAA, and 2-NAA. With MSN@MIL-101(Fe) as sorbent for extraction of Phys and determination by HPLC-DAD, two endogenous Phys (IAA and ABA) were detected from mung bean sprouts which were made in a laboratory, and the results were further confirmed by high-resolution mass spectrometry. The composites can be applied to extract other small molecules, which have similar chemical structures with Phys in biological, environmental, and food samples. Graphical abstract Schematic presentation of a dispersive solid-phase extraction using monodispersed mesoporous SiO2@metal-organic framework composites (MSNs@MIL-101(Fe)) as the sorbent for extraction, clean-up, and preconcentration of phytohormones in mung bean sprouts prior to HPLC-DAD analysis.
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Glucose metabolic reprogramming is a hallmark of cancer. Cancer cells rapidly adjust their energy source from oxidative phosphorylation to glycolytic metabolism in order to efficiently proliferate in a hypoxic environment, but the mechanism underlying this switch is still incompletely understood. Here, we report that hypoxia potently induces the RNA-binding protein HuR to specifically bind primary miR-199a transcript to block miR-199a maturation in hepatocellular carcinoma (HCC) cells. We demonstrate that this hypoxia-suppressed miR-199a plays a decisive role in limiting glycolysis in HCC cells by targeting hexokinase-2 (Hk2) and pyruvate kinase-M2 (Pkm2). Furthermore, systemically delivered cholesterol-modified agomiR-199a inhibits [(18)F]-fluorodeoxyglucose uptake and attenuates tumor growth in HCC tumor-bearing mice. These data reveal a novel mechanism of reprogramming of cancer energy metabolism in which HuR suppresses miR-199a maturation to link hypoxia to the Warburg effect and suggest a promising therapeutic strategy that targets miR-199a to interrupt cancerous aerobic glycolysis.
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Carcinoma Hepatocelular/genética , Proteína 1 Similar a ELAV/fisiología , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , MicroARNs/genética , Animales , Secuencia de Bases , Carcinoma Hepatocelular/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Hipoxia de la Célula , Línea Celular Tumoral , Glucólisis , Hexoquinasa/genética , Hexoquinasa/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/metabolismo , Trasplante de Neoplasias , Unión Proteica , Hormonas Tiroideas/genética , Hormonas Tiroideas/metabolismo , Proteínas de Unión a Hormona TiroideRESUMEN
Mesoporous graphitic carbon nitride (MCN) is shown to be a viable sorbent for the enrichment of sulfonamides (SAs). To overcome the difficulty of separating the sorbent from the matrix, a novel type kind of column-assisted dispersive solid-phase extraction (CA-dSPE) method was designed. The MCN was characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy and nitrogen adsorption-desorption measurements. The amount of sorbent, the pH value of the sample, the adsorption time, type and volume of the eluent and desorption time were optimized. The SAs were eluted from the sorbent with elution solvent of methanol containing 10% (v/v) ammonia and then submitted to HPLC analysis. Under the optimized conditions, the limits of detection for the SAs investigated (sulfadiazine, sulfameter, sulfachloropyridazine, sulfabenzamide and sulfadimethoxine) range from 20 to 5 pg·mL-1. Satisfactory recoveries were obtained for spiked environmental water (90.1-110.5%) and milk samples (82.3-102.7%), with relative standard deviations of 0.5-3.8% and 1.1-4.4%, respectively. The method is simple, time saving and sensitive. Graphical abstract Schematic presentation of a column assisted dispersive solid-phase extraction by using mesoporous graphitic carbon nitride as sorbent combined with high performance liquid chromatography for sensitive analysis of sulfonamides in environmental water and milk samples.
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An electrochemical sensing platform was designed to monitor telomerase activity in HeLa cells, using bioresponsively controlled cargo release from magnetic mesoporous silica nanocontainers (MMSNs). The aminated MMSNs were first synthesized by a wet-chemistry method, then methylene blue (indicator) molecules were loaded into the pores with the aid of specifically designed wrapping DNA strands, and then the wrapping DNA-gated MMSNs were immobilized on a magnetic removable screen-printing carbon electrode. Upon target telomerase and dNTP introduction into the detection cell, the wrapping DNA strands on the MMSNs were prolonged to form rigid hairpin-like DNA structures, thus resulting in the dissociation of wrapping DNA strands from the MMSNs. Thereafter, the loaded methylene blue with redox activity was released out from the pores, thereby causing the increase in the electrochemical signal relative to the background signal. Under optimal conditions, an MMSN-based sensing system exhibited good voltammetric responses toward target telomerase activity within the dynamic linear range of 50-5000 cells per mL at a detection limit of 12 cells per mL in the HeLa extract. The reproducibility and generality of our strategy were acceptable by using somatic tumor cell lines. In addition, the inhibition effect of this system was also evaluated by using 3'-azido-3'-deoxythymidine as a telomerase inhibitor, receiving good results in this screening research.
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Técnicas Electroquímicas , Azul de Metileno/química , Dióxido de Silicio/química , Telomerasa/análisis , Técnicas Biosensibles , ADN/química , Células HeLa , Humanos , Nanopartículas , Reproducibilidad de los ResultadosRESUMEN
Herein, a simple and feasible electrochemical immunosensing method for simultaneous voltammetric detection of two immunoglobulin proteins, human IgG (HIgG) and rabbit IgG (RIgG), was developed using two distinguishable signal-generation tags on the same electrode. The immunosensor was prepared by immobilizing two Fab antibody fragments on a gold electrode. After this, Cu and Cd nanocrystals, as nanotags, were synthesized and functionalized with identical detection antibodies. Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the Cu and Cd nanocrystals. The covalently modified electrode with the Fab antibody fragments through the Au-thiolate bond (to dispel the non-specific adsorption) was investigated via scanning electron microscopy (SEM). After the sandwiched immunoreaction, the antibody-modified nanocrystals were captured on the immunosensor, which could be interrogated in pH 3.5 HCl using square-wave anodic stripping voltammetry. Experimental results also indicated that the multiplexed immunoassay enabled the simultaneous detection of HIgG and RIgG in a single run with the similar linear range from 0.01 to 10 ng mL-1, and the limits of detection (LODs) towards two analytes could be as low as 3.4 pg mL-1 (at 3σ). Acceptable assay results on precision, reproducibility, specificity, and method accuracy were also acquired. Importantly, the newly designed strategy avoided cross-talk and enzymatic introduction as compared to conventional electrochemical immunoassays, thus exhibiting a promising potential in clinical applications.
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Técnicas Electroquímicas , Inmunoensayo , Inmunoglobulina G/análisis , Nanopartículas del Metal , Animales , Anticuerpos Inmovilizados , Técnicas Biosensibles , Cadmio , Cobre , Electrodos , Oro , Humanos , Fragmentos Fab de Inmunoglobulinas , Límite de Detección , Conejos , Reproducibilidad de los ResultadosRESUMEN
A simple and practical method for I2-mediated one-pot synthesis of 3-alkyl-5-aryl-1,2,4-thiadiazoles has been developed; the one-pot reaction includes sequential intermolecular addition of thioamides to nitriles, and intramolecular oxidative coupling of N-H and S-H bonds mediated by molecular iodine. Meanwhile the protocol uses readily available nitriles and thioamides as the starting materials, molecular iodine as the oxidant, and generates various 1,2,4-thiadiazoles in moderate to good yields with a wide array of functional groups. This method is an efficient approach for the synthesis of unsymmetrically disubstituted 1,2,4-thiadiazoles.
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A rapid and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of two baccharane glycosides (hosenkoside A and hosenkoside K) of total saponins of Semen Impatientis in rat plasma using mogroside V as the internal standard (IS). The analytes were separated using a C18 RP Agilent XDB column (1.8 µm, 50 × 2.1 mm i.d.) and detection of the compounds was done using a TSQ Quantum triple quadrupole mass spectrometer coupled with a negative electrospray ionization source under selection reaction monitoring mode. According to the US Food and Drug Administration guidelines, the established method was fully validated and the results were proved within acceptable limits. The lower limits of quantification of both analytes were 5 ng/mL. The validated method was successfully applied to a pharmacokinetic study of orally administered the total saponins of Semen Impatientis in rats.
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Análisis Químico de la Sangre/métodos , Cromatografía Liquida , Medicamentos Herbarios Chinos/análisis , Espectrometría de Masas en Tándem , Animales , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacocinética , Masculino , Ratas , Ratas Sprague-Dawley , Saponinas/análisis , Saponinas/farmacocinética , Triterpenos/análisis , Triterpenos/farmacocinéticaRESUMEN
Cancer cells preferentially metabolize glucose through aerobic glycolysis. This phenomenon, known as the Warburg effect, is an anomalous characteristic of glucose metabolism in cancer cells. Chronic inflammation is a key promoting factor of tumourigenesis. It remains, however, largely unexplored whether and how pro-tumourigenic inflammation regulates glucose metabolism in cancer cells. Here, we show that pro-inflammatory cytokines promote glycolysis in breast cancer cells, and that the inflammation-induced miR-155 functions as an important mediator in this process. We further show that miR-155 acts to upregulate hexokinase 2 (hk2), through two distinct mechanisms. First, miR-155 promotes hk2 transcription by activation of signal transducer and activator of transcription 3 (STAT3), a transcriptional activator for hk2. Second, via targeting C/EBPß (a transcriptional activator for mir-143), miR-155 represses mir-143, a negative regulator of hk2, thus resulting in upregulation of hk2 expression at the post-transcriptional level. The miR-155-mediated hk2 upregulation also appears to operate in other types of cancer cells examined. We suggest that the miR-155/miR-143/HK2 axis may represent a common mechanism linking inflammation to the altered metabolism in cancer cells.
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Glucólisis , Hexoquinasa/biosíntesis , MicroARNs/metabolismo , Animales , Neoplasias de la Mama/fisiopatología , Línea Celular Tumoral , Humanos , RatonesRESUMEN
Herein a novel split-type photoelectrochemical (PEC) immunosensing platform was designed for sensitive detection of low-abundance biomarkers (prostate-specific antigen, PSA, used in this case) by coupling a peroxyoxalate chemiluminescence (PO-CL) self-illuminated system with digital multimeter (DMM) readout. The PEC detection device consisted of a capacitor/DMM-joined electronic circuit and a PO-CL-based self-illuminated cell. Initially, reduced graphene oxide-doped BiVO4 (BiVO4-rGO) photovoltaic materials with good photoelectric properties was integrated into the capacitor/DMM-joined circuit for photocurrent generation in the presence of hydrogen peroxide (H2O2, as the hole-trapping reagent). A sandwich-type immunoreaction with target PSA was carried out in capture antibody-coated microplates by using glucose oxidase/detection antibody-conjugating gold nanoparticle (pAb2-AuNP-GOx). Accompanying the sandwiched immunocomplex, the labeled GOx could oxidize glucose to produce H2O2. The as-generated H2O2 could act as the coreaction reagent to trigger the chemiluminescence of the peroxyoxalate system and the PEC reaction of the BiVO4-rGO. Meanwhile, the self-illuminated light could induce photovoltaic material (BiVO4-rGO) to produce a voltage that was utilized to charge an external capacitor. With the switch closed, the capacitor could discharge through the DMM and provide an instantaneous current. Different from conventional PEC immunoassays, the as-generated photoelectron was stored in the capacitor and released instantaneously to amplify the photocurrent. Under the optimal conditions, the transient current increased with the increasing target PSA concentration in the dynamic working range from 10 pg mL(-1) to 80 ng mL(-1) with a detection limit (LOD) of 3 pg mL(-1). This work demonstrated for the first time that the peroxyoxalate CL system could be used as a suitable substitute of physical light source to apply in PEC immunoassay. In addition, this methodology afforded good reproducibility, precision, and high specificity, and the method accuracy matched well with the commercial PSA ELISA kit. Importantly, the developed split-type photoelectrochemical immunoassay could not only avoid the interfering of the biomolecules relative to the photovoltaic materials but also eliminate the need of an exciting light source and expensive instrumentation, thus representing a user-friendly and low-cost assay protocol for practical utilization in quantitative low-abundance proteins.
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Enzimas/metabolismo , Inmunoensayo/métodos , ElectroquímicaRESUMEN
A label-free hyperbranched rolling circle amplification (HRCA) based fluorescent sensor has been developed for Hg(2+) detection. The fluorescence intensity has a linear relationship with the concentration of the target in the range of 0.425 pmol L(-1) to 42.5 nmol L(-1), and the detection limit is as low as 0.14 pmol L(-1) (S/N = 3). The proposed sensor had been applied to detect Hg(2+) in water samples with satisfying results.
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Técnicas Biosensibles/métodos , Colorantes Fluorescentes/química , Mercurio/análisis , Técnicas de Amplificación de Ácido Nucleico/métodos , Contaminantes Químicos del Agua/análisis , Agua/química , Fluorescencia , Límite de DetecciónRESUMEN
A target-initiated proximity ligation assay (PLA) protocol accompanying DNAzyme formation was for the first time designed for ultrasensitive impedimetric monitoring of heavy metal ions (silver ions were used in this case) by coupling with enzymatic biocatalytic precipitation.
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ADN Catalítico/química , Biocatálisis , Microscopía de Fuerza AtómicaRESUMEN
The sensitive detection of polychlorinated biphenyls (PCBs) is crucial for protecting the environment and human health. Herein, we constructed a Materials Institute Lavoisier 88B (MIL-88B)-on-University of Oslo 66 (UiO-66) composite (MIL-on-UiO) with a unique nanoflower morphology, in which highly stable UiO-66 is the precursor, with MIL-88B grown on its surface. MIL-on-UiO was used as a fiber coating for headspace solid-phase microextraction to enrich PCBs. Experimental results demonstrated that MIL-on-UiO provided better enrichment performance for PCBs than single components due to multiple interactions, including π-π stacking, halogen bonding, pore-filling, and steric hindrance effects. The method established using the MIL-on-UiO-based SPME fiber coating provided a good linear relationship in the range of 0.001-50 ng·mL-1, with limits of detection ranging from 0.0002 to 0.002 ng·mL-1 and enrichment factors between 3530 and 7420. In addition, the method was used to detect trace PCBs in water and orange juice achieving satisfactory recoveries (81%-111%).
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Contaminación de Alimentos , Bifenilos Policlorados , Microextracción en Fase Sólida , Bifenilos Policlorados/análisis , Bifenilos Policlorados/química , Microextracción en Fase Sólida/métodos , Contaminación de Alimentos/análisis , Límite de Detección , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Estructuras Metalorgánicas/química , Bebidas/análisisRESUMEN
The improvement of the stability and adsorption properties of materials on targets in sample pre-treatment has long been an objective. Extensive efforts have been made to achieve this goal. In this work, metal-organic framework Ni-MOF precursors were first synthesized by solvothermal method using polyvinylpyrrolidone (PVP) as an ideal templating agent, stabiliser and nanoparticle dispersant. After carbonization and acid washing, the nanoporous carbon microspheres material (Ni@C-acid) was obtained. Compared with the material without acid treatment (Ni@C), the specific surface area, pore volume, adsorption performance of Ni@C-acid were increased. Thanks to its excellent characteristics (high stability, abundant benzene rings), Ni@C-acid was used as fiber coatings in headspace solid-phase microextraction (HS-SPME) technology for extraction and preconcentration of polycyclic aromatic hydrocarbons (PAHs) prior to gas chromatography-flame ionization detector (GC-FID) analysis. The experimental parameters of extraction temperature, extraction time, agitation speed, desorption temperature, desorption time and sodium chloride (NaCl) concentration were studied. Under optimal experimental conditions, the wide linear range (0.01-30 ng mL-1), the good correlation coefficient (0.9916-0.9984), the low detection limit (0.003-0.011 ng mL-1), and the high enrichment factor (5273-13793) were obtained. The established method was successfully used for the detection of trace PAHs in actual tea infusions samples and satisfied recoveries ranging from 80.94-118.62 % were achieved. The present work provides a simple method for the preparation of highly stable and adsorbable porous carbon microsphere materials with potential applications in the extraction of environmental pollutants.
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Carbono , Límite de Detección , Estructuras Metalorgánicas , Microesferas , Hidrocarburos Policíclicos Aromáticos , Microextracción en Fase Sólida , Té , Microextracción en Fase Sólida/métodos , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Hidrocarburos Policíclicos Aromáticos/análisis , Té/química , Carbono/química , Estructuras Metalorgánicas/química , Porosidad , Adsorción , Níquel/química , Níquel/aislamiento & purificación , Cromatografía de Gases/métodos , Reproducibilidad de los ResultadosRESUMEN
Based on multiple ligands strategy, a series of multivariate metal organic frameworks (MTV-MOFs) named as PCN-224-DCDPSx were prepared using one-pot solvothermal method to extract and remove sulfonamide antibiotics (SAs). The pore structure and adsorption performance can be further regulated by modulating the doping ratios of medium-tetra(4-carboxylphenyl) porphyrin and 4,4'-dicarboxydiphenyl sulfones. The MTV-MOFs of PCN-224-DCDPS1.0 possesses very large specific surface area (1625 m2/g). Using PCN-224-DCDPS1.0 as sorbent, a dispersive solid-phase extraction method was developed to extract and preconcentrate SAs from water, eggs, and milk prior to high performance liquid chromatography analysis. The limits of detection of method were determined between 0.17 and 0.27 ng/mL with enrichment factors ranging 214-327. The adsorption can be finished within 30 s, and the recovery rate remains above 80 % after 10 repeated uses. The adsorption capacities of sorbent were determined from 300 to 621 mg/g for sulfadiazine, sulphapyridine, sulfamethoxydiazine, sulfachlorpyridazine, sulfabenzamide, and sulfadimethoxine. The adsorption mechanisms were investigated and can be attributed to π-π interactions, hydrogen bonds, and electrostatic interactions. This work represents a method for preparation of MTV-MOFs and uses as sorbent for extraction and enrichment of trace pollutants from complex samples.
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Antibacterianos , Contaminación de Alimentos , Estructuras Metalorgánicas , Leche , Extracción en Fase Sólida , Sulfonamidas , Contaminantes Químicos del Agua , Sulfonamidas/química , Sulfonamidas/aislamiento & purificación , Sulfonamidas/análisis , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/análisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Adsorción , Estructuras Metalorgánicas/química , Extracción en Fase Sólida/métodos , Leche/química , Contaminación de Alimentos/análisis , Circonio/química , Animales , Huevos/análisis , Cromatografía Líquida de Alta PresiónRESUMEN
The Microsoft Kinect depth sensor, with its built-in software that automatically captures joint coordinates without markers, could be a potential tool for ergonomic studies. This study investigates the performance of Kinect in limb segment lengths using dual-energy X-ray absorptiometry (DXA) as a reference. Healthy children and adults (n = 76) were recruited for limb length measurements by Kinect and DXA. The results showed consistent ratios of arm, forearm, thigh, and leg lengths to height, which were 0.16, 0.14, 0.23, and 0.22 respectively, for both age groups and methods. Kinect exhibited perfect correlation among all limb lengths, indicating fixed proportions assumed by its algorithm. Comparing the two methods, there was a strong correlation (R = 0.850-0.985) and good to excellent agreement (ICC = 0.829-0.977), except for the right leg in adults, where agreement was slightly lower but still moderate (ICC = 0.712). The measurement bias between the methods ranged from - 1.455 to 0.536 cm. In conclusion, Kinect yields outcomes similar to DXA, indicating its potential utility as a tool for ergonomic studies. However, the built-in algorithm of Kinect assumes fixed limb proportions for individuals, which may not be ideal for studies focusing on investigating limb discrepancies or anatomical differences.
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Absorciometría de Fotón , Humanos , Adulto , Masculino , Niño , Femenino , Absorciometría de Fotón/métodos , Adulto Joven , Algoritmos , Programas Informáticos , Adolescente , Persona de Mediana Edad , Antropometría/métodosRESUMEN
We here report that miR-17-92 cluster is a novel target for p53-mediated transcriptional repression under hypoxia. We found the expression levels of miR-17-92 cluster were reduced in hypoxia-treated cells containing wild-type p53, but were unchanged in hypoxia-treated p53-deficient cells. The repression of miR-17-92 cluster under hypoxia is independent of c-Myc. Luciferase reporter assays mapped the region responding to p53-mediated repression to a p53-binding site in the proximal region of the miR-17-92 promoter. Chromatin immunoprecipitation (ChIP), Re-ChIP and gel retardation assays revealed that the binding sites for p53- and the TATA-binding protein (TBP) overlap within the miR-17-92 promoter; these proteins were found to compete for binding. Finally, we show that pri-miR-17-92 expression correlated well with p53 status in colorectal carcinomas. Over-express miR-17-92 cluster markedly inhibits hypoxia-induced apoptosis, whereas blocked miR-17-5p and miR-20a sensitize the cells to hypoxia-induced apoptosis. These data indicated that p53-mediated repression of miR-17-92 expression likely has an important function in hypoxia-induced apoptosis, and thus further our understanding of the tumour suppressive function of p53.