RESUMEN
BACKGROUND: Apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) is a promising stroke biomarker. However, a large study of human serum ASC has not yet to be reported; additionally, the diagnostic value of prehospital concentration and practicality of ASC remains unknown. METHODS: We recruited 774 Chinese stroke patients, including 523 with ischemic stroke (IS) and 251 with hemorrhagic stroke (HS) within 14 days following symptom onset in the emergency department, alongside 481 healthy individuals and 64 cognitive impairment patients as controls. Serum ASC concentrations were determined using automated chemiluminescence immunoassay, exploring the relationship between serum ASC concentration and subtypes, severity, and sampling timepoints of stroke. RESULTS: ASC concentrations were significantly higher in stroke patients compared with all controls (P < 0.001). HS patients had greater ASC concentrations than IS patients (P < 0.05). With increasing ASC concentration, the proportion of severe cases increased. The area under the receiver operating characteristic curve (AUC) for differentiating between healthy individuals and stroke patients in the hyperacute phase was 0.78; this markedly improved (0.90) when considering samples from healthy individuals and patients with subarachnoid hemorrhage (SAH) ≤ 3 h from last-known-well (LKW). CONCLUSIONS: Serum ASC is a valuable biomarker for stroke differentiation and aids in the clinical diagnosis of stroke severity and subtypes.
Asunto(s)
Proteínas Adaptadoras de Señalización CARD , Accidente Cerebrovascular , Humanos , Apoptosis , Biomarcadores , Caspasas , Accidente Cerebrovascular/diagnósticoRESUMEN
In forensic investigations, age estimation is vital for determining whether a suspect is under or over the legally defined adult age. With breakthroughs in RNA sequencing technology, small noncoding RNAs have provided new ways to solve problems related to the age estimation of trace or aged samples, owing to their small molecular weight and better stability. In our previous study, we had applied miRNAs for the age estimation of bloodstains; however, further improvement of the existing model is needed. PIWI-interacting RNAs (PiRNAs), which are 24-32 nt noncoding small RNA molecules involved in the PIWI-piRNA pathway, play an important role in the aging process. In this study, we explored the possibility of simultaneously analyzing piRNAs and miRNAs for better age estimation purpose. Through massively parallel sequencing, five age-related piRNAs were identified in blood samples that had been stored for eight years. Further real-time PCR analysis revealed that two piRNAs (piR-000753 and piR-020548) showed relatively higher efficiency in age estimation. Additionally, two age-related miRNAs (miR-324-3p and miR-330-5p) were used to build the estimation model. Among all algorithms tested, gradient boosting showed the lowest mean absolute error (MAE) and root mean square error (RMSE) values (3.171 and 4.403 years, respectively) for the validation dataset (n = 110). The errors of the model were less than 5 years and 10 years for 81.82% and 96.36% of the samples, respectively. The results suggest that the combined use of piRNA and miRNA markers may increase the accuracy of age estimation, and our new model has great potential for application in forensic casework.
Asunto(s)
Manchas de Sangre , MicroARNs , ARN Pequeño no Traducido , Humanos , Adulto , Anciano , Niño , MicroARNs/genética , ARN de Interacción con Piwi , ARN Interferente Pequeño/genéticaRESUMEN
Diosgenin, a steroidal sapogenin, has attracted attention worldwide owing to its pharmacological properties, including antitumor, cardiovascular protective, hypolipidemic, and anti-inflammatory effects. The current diosgenin analysis methods have the disadvantages of long analysis time and low sensitivity. The aim of the present study was to establish an efficient, sensitive ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) approach for pharmacokinetic analysis of diosgenin amorphous solid dispersion (ASD) using tanshinone IIA as an internal standard (IS). Male Sprague-Dawley rats were orally administered diosgenin ASD, and orbital blood samples were collected for analysis. Protein precipitation was performed with methanol-acetonitrile (50 : 50, v/v), and the analytes were separated under isocratic elution by applying acetonitrile and 0.03% formic acid aqueous solution at a ratio of 80 : 20 as the mobile phase. MS with positive electron spray ionization in multiple reaction monitoring modes was applied to determine diosgenin and IS with m/z 415.2â¶271.2 and m/z 295.2â¶277.1, respectively. This approach showed a low limit of quantification of 0.5 ng/ml for diosgenin and could detect this molecule at a concentration range of 0.5 to 1,500 ng/ml (r = 0.99725). The approach was found to have intra- and inter-day precision values ranging from 1.42% to 6.91% and from 1.25% to 3.68%, respectively. Additionally, the method showed an accuracy of -6.54 to 4.71%. The recoveries of diosgenin and tanshinone IIA were 85.81-100.27% and 98.29%, respectively, with negligible matrix effects. Diosgenin and IS were stable under multiple storage conditions. Pharmacokinetic analysis showed that the C max and AUC0â¶t of diosgenin ASD were significantly higher than those of the bulk drug. A sensitive, simple, UPLC-MS/MS analysis approach was established and used for the pharmacokinetic analysis of diosgenin ASD in rats after oral administration.
RESUMEN
Polychlorinated biphenyls (PCBs) are persistent organic pollutants which are widely present in environment and harmful to human health. In this study, an efficient and convenient magnetic solid phase extraction method with C60 modified magnetic polyamido-amine (PAMAM) dendrimers as sorbents was established for enriching trace amounts of PCBs in beverage samples. Gas chromatography-tandem mass spectrometry (GC-MS/MS) was utilized for analysis of PCBs. Parameters affecting extraction efficiency were optimized. Under optimal parameters, good linearity can be achieved in concentration range of 0.001-20 µg L-1 and 0.002-20 µg L-1 for nine selected PCBs. The limits of detection for PCBs were in the range of 0.1-0.2 ng L-1. The spiked recoveries were in the range of 87.0 %-115.1 % (n = 3). The results proved that this established method was reliable for monitoring trace PCBs in beverage samples.
Asunto(s)
Dendrímeros , Bifenilos Policlorados , Aminas/análisis , Bebidas/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Fenómenos Magnéticos , Bifenilos Policlorados/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodosRESUMEN
INTRODUCTION: Orthodontic treatment and adenotonsillectomy (AT) are both conventional treatments for paediatric obstructive sleep apnoea (OSA). Each approach has distinct treatment advantages; however, there is currently a lack of solid evidence to support their efficacy comparison. We hypothesise that the objective effect of orthodontic treatment is not inferior to AT in children with moderate OSA and mandibular retrognathia, but orthodontic treatment has the advantage of promoting dentofacial growth. METHODS AND ANALYSIS: This is a randomised, open-label, parallel-group, active controlled trial that will study the efficacy of orthodontic treatment versus AT in children with moderate OSA accompanied by tonsillar adenoid hypertrophy and mandibular retrognathia. A total of 98 patients will be enrolled and randomised in a 2:1 ratio to either orthodontic treatment or AT group. Participants will be recruited at Shanghai Stomatological Hospital, Shanghai Children's Hospital of Shanghai Jiaotong University and Children's Hospital of Fudan University, which are all located in Shanghai, China. The primary endpoint is the per cent change in the obstructive apnoea-hypopnoea index from baseline (month 0) to the primary endpoint (month 7), and the mean reduction in A point, nasion and B point angle on cephalometric measurements by lateral X-ray films. Important secondary efficacy endpoints include sleep duration with oxygen saturation below 90% according to polysomnography and subjective symptoms (assessed by the OSA-20 questionnaire), etc. Safety endpoints will also be evaluated. ETHICS AND DISSEMINATION: The study was approved by the ethics committees of Shanghai Stomatological Hospital (approval no. (2021)002), Shanghai Children's Hospital of Shanghai Jiaotong University (approval no. 2021R046-F01) and Children's Hospital of Fudan University (approval no. (2021)136). Before enrolment, a qualified clinical research assistant will obtain written informed consent from both the participants and their guardians after full explanation of this study. The results will be presented at national or international conferences and published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ChiCTR2000037288.
Asunto(s)
Retrognatismo , Apnea Obstructiva del Sueño , Tonsilectomía , Adenoidectomía , Niño , China , Humanos , Hipertrofia , Ensayos Clínicos Controlados Aleatorios como Asunto , Retrognatismo/complicaciones , Apnea Obstructiva del Sueño/cirugíaRESUMEN
Present work depicted a novel electrochemical sensor fabricated with magnetic carbon dots (M-CDs) and cetyltrimethylammonium bromide (CTAB) modified glassy carbon electrode (GCE) for selective measurement of 3,3',5,5'-tetrabromobisphenol A (TBBPA) in beverages. The M-CDs composite material revealed good electrocatalytic activity, and CTAB has strong hydrophobic interaction which enable it have good enrichment capacity of hydrophobic compounds, and combination of them further enhances the electrochemical signal. Hence CTAB decoration can markedly improve the detection performance of TBBPA. Electrochemical properties of the fabricated sensor was investigated through performing cyclic voltammetry (CV). The morphology and functional groups of the modified materials were examined with transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). The results indicated that the synthesized material had a spherical-like structure, good dispersion properties and plenty of functional groups on the surface. The effects of incubation potential, incubation time, pH of electrolyte, and scanning rate on oxidation peak current were investigated. Under optimal conditions, the designed sensor had good linear range of 1 nM-1000 nM, and the detection of limit of the constructed sensor was 0.75 nM. The constructed sensor was utilized to detect TBBPA in vitamin water, scream drink and genki forest, and satisfactory detection performance had been achieved.
Asunto(s)
Carbono , Técnicas Electroquímicas , Bebidas , Carbono/química , Cetrimonio , Técnicas Electroquímicas/métodos , Electrodos , Límite de Detección , Fenómenos Magnéticos , Bifenilos PolibrominadosRESUMEN
Polychlorinated biphenyls (PCBs) are a kind of hazardous persistent organic contaminants and widely present in nature due to large consumption in the past. Although PCBs have been banned in many countries of the world, they are still present at trace level in food and water samples. It is of significant value to establish reliable enrichment and detection method. Based on the conversion of the hydrophilicity and hydrophobicity from heptanoic acid under alkali and acid, increasing the contact area between heptanoic acid and PCBs, a new switchable solvent micro-extraction method for PCBs from beverages was developed with good extraction efficiency using heptanoic acid as the extractant prior to gas chromatography-tandem mass spectrometry (GC-MS/MS). The key parameters that had impact on enrichment of PCBs were investigated in detail. Under the optimal conditions, a good linearity can be achieved in a concentration range of 0.01-20 µg L-1 with the correlation coefficients of 0.9978-0.9994. Limits of detection for PCB28, PCB53, PCB206 were 3 ng L-1 and PCB118 was 5 ng L-1 while other target PCBs were 2 ng L-1. Intra-day and inter-day precisions were in the range of 1.9-4.2% and 2.1-4.2ï¼ (relative standard deviation, RSD, n = 6), respectively. The real sample spiked recoveries of the targets were in the range of 93.2-114.3ï¼ (n = 3). The enrichment factors were in the range of 16.2-17.9. The results proved that this method was reliable for monitoring trace PCBs in beverage samples and will help for future assessments of impacts on human and animal health.
Asunto(s)
Bifenilos Policlorados , Animales , Bebidas/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Bifenilos Policlorados/análisis , Solventes/análisis , Espectrometría de Masas en TándemRESUMEN
In this study, graphene oxide modified magnetic polyamidoamine dendrimers (MNPs@PAMAM-G2.0@GO) nanoparticles were successfully prepared by amidation method. The obtained MNPs@PAMAM-G2.0@GO nanocomposites were examined by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscope (SEM) and transmission electron microscopy (TEM), etc. MNPs@PAMAM-G2.0@GO exhibited excellent adsorption property and was investigated for magnetic solid phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) from water. The detection of extracted PAHs was accomplished by high performance liquid chromatography (HPLC) and gas chromatography tandem mass spectrometry (GC-MS/MS). The target PAHs included anthracene (ANT), pyrene (PYR), fluoranthene (FLT), carbazole (CB), 7-methylquinoline (7-MQL), 9-methylcarbazole (9-MCB), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DBT). Important operation parameters for MSPE that could affect the extraction efficiencies of PAHs were investigated in detail. Under optimal parameters, the constructed method demonstrated excellent linear range with 0.001-10 µg L-1 for analytes and low limits of detection within the range of 0.11-0.9 ng L-1. The spiked average recoveries of PAHs in natural water samples ranged from 92.5% to 105.2%. The promising results indicated that MNPs@PAMAM-G2.0@GO could be employed to efficiently extract PAHs from aqueous samples.
Asunto(s)
Dendrímeros , Hidrocarburos Policíclicos Aromáticos , Adsorción , Dendrímeros/química , Cromatografía de Gases y Espectrometría de Masas , Grafito , Límite de Detección , Fenómenos Magnéticos , Hidrocarburos Policíclicos Aromáticos/análisis , Extracción en Fase Sólida/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Masas en Tándem , AguaRESUMEN
The global effort against the COVID-19 pandemic dictates that routine quantitative detection of SARS-CoV-2 neutralizing antibodies is vital for assessing immunity following periodic revaccination against new viral variants. Here, we report a dual-detection fluorescent immunochromatographic assay (DFIA), with a built-in self-calibration process, that enables rapid quantitative detection of neutralizing antibodies that block binding between the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein and the angiotensin-converting enzyme 2 (ACE2). Thus, this assay is based on the inhibition of binding between ACE2 and the RBD of the SARS-CoV-2 spike protein by neutralizing antibodies, and the affinity of anti-human immunoglobulins for these neutralizing antibodies. Our self-calibrating DFIA shows improved precision and sensitivity with a wider dynamic linear range, due to the incorporation of a ratiometric algorithm of two-reverse linkage signals responding to an analyte. This was evident by the fact that no positive results (0/14) were observed in verified negative samples, while 22 positives were detected in 23 samples from verified convalescent plasma. A comparative analysis of the ability to detect neutralizing antibodies in 266 clinical serum samples including those from vaccine recipients, indicated that the overall percent agreement between DFIA and the commercial ELISA kit was 90.98%. Thus, the proposed DFIA provides a more reliable and accurate rapid test for detecting SARS-CoV-2 infections and vaccinations in the community. Therefore, the DFIA based strategy for detecting biomarkers, which uses a ratiometric algorithm based on affinity and inhibition reactions, may be applied to improve the performance of immunochromatographic assays.
Asunto(s)
Técnicas Biosensibles , COVID-19 , Enzima Convertidora de Angiotensina 2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/terapia , Humanos , Inmunización Pasiva , Inmunoensayo , Pandemias , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Sueroterapia para COVID-19RESUMEN
Objective @#To evaluate the morphology of the upper airway of children with obstructive sleep apnea-hypopnea syndrome (OSAHS) using cone-beam computed tomography (CBCT) combined with polysomnography (PSG) and provide references for clinical practice.@*Methods@# CBCT data of 45 OSAHS children and 45 normal children and PSG data of the OSAHS group were retrospectively collected. Three-dimensional reconstructions were performed using NNT 9.0 software. The total upper airway volume, nasopharyngeal volume, palatopharyngeal volume, glossopharyngeal volume, laryngopharyngeal volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section, and lateral diameter of the minimum cross-section were measured and recorded. According to PSG monitoring results, patients with an obstructive apnea hypopnea index (OAHI) and lowest oxygen saturation (LSaO2) were assessed. Body mass index (BMI) was recorded. The correlation between airway volume parameters, BMI and PSG test results was analyzed. @*Results@#The total upper airway volume, nasopharyngeal volume, palatopharyngeal volume, glossopharyngeal volume, laryngopharyngeal volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section, and lateral diameter of the minimum cross-section of the OSAHS group were significantly reduced compared with those of the control group (P<0.05). In the OSAHS group, the total upper airway volume, the minimum cross-sectional area and the lateral diameter of the minimum cross-section showed moderate negative correlations with the obstructive apnea hypopnea index (OAHI) (P<0.05). Moreover, the total upper airway volume, minimum cross-sectional area, anterior-posterior diameter of the minimum cross-section and lateral diameter of the minimum cross-section showed no correlation with the minimum blood oxygen saturation (P>0.05). No significant correlation was noted between BMI and PSG in the OSAHS group (P>0.05).@*Conclusion @#The morphology of the upper airway of children with OSAHS was significantly smaller than that of normal children. CBCT three-dimensional technology for analyzing the upper airway has a certain value in evaluating the morphology and degree of obstruction of the upper airway in children with OSAHS.
RESUMEN
The health threat from Sudan red dyes has been the subject of much attention in recent years and is crucial to design and establish reliable measurement technologies. In the present study, a new magnetic nanomaterial, polyamidoamine dendrimer-modified magnetic nanoparticles (Gn-MNPs), was synthesized and characterized. The nanomaterials had good adsorption capacity for Sudan dyes from natural waters. G1.5-MNPs possessed excellent adsorption capacity and a linear adsorption relationship over the range from 0.02 to 300 µg L-1 of Sudan dyes with relative coefficients all larger than 0.996. The sensitivity of the proposed method was excellent with detection limits over the range from 1.8 to 5.5 ng L-1 and the precision was less than 3.0%. G1.5-MNPs showed a remarkable application potential for the enrichment of trace environment pollutants in aqueous samples and the developed method based on this nanomaterial could be a robust and reliable alternative tool for routine monitoring of such pollutants.
RESUMEN
A new kind of nitrogen-doped carbon dots (N-CDs) was synthesized via a simple hydrothermal strategy using humic acid as the carbon source and urea as the nitrogen source. The fluorescence intensity of as-prepared N-CDs was quenched significantly in presence of Cu2+ based on a specific inner filter effect, which could be utilized to construct a selective sensor for monitoring Cu2+ in aqueous samples. The sensor exhibited good linearity over the range of 0.1-2 µM, and high sensitivity with a detection limit of 25 nM. Under the optimal conditions, there was no significant interference by other metal ions such as Cd2+, Al3+, Cr3+, Fe3+, Pb2+, Na+, Ni+, Fe2+, Ba2+, Ca2+, Co2+, Mg2+, As3+, K+, Zn2+ for Cu2+ detecting except Hg2+.The interference of Hg2+ can be masked by addition of sodium chloride. The experimental results demonstrated that the prepared N-CDs owned strong fluorescence, high monodispersity, good stability and good water solubility, and the constructed sensor had many advances and great application prospect in environmental field.
Asunto(s)
Carbono , Puntos Cuánticos , Sustancias Húmicas , Nitrógeno , Espectrometría de Fluorescencia , UreaRESUMEN
Carbon dots have been a promising nano-carbon material with many advantages, and attracted many more attentions. This study designed a new chemosensor integrating the strong fluorescent property of carbon dots and the magnetism of amino-functionalized magnetic core-shell nanomaterial, Fe@SiO2-NH2 for determination of 2,4,6-trinitrotoluene (TNT). In this system, fluorescent carbon dots interacted with amino groups on the surface of amino-functionalized magnetic core-shell nanomaterial leading to fluorescence quenching of carbon dots, appearance of TNT competitively replaced of carbon dots on the surface of the magnetic material through forming a Meisenheimer complex. This sensor exhibits excellent selectivity and sensitivity for TNT, and which provided a good dynamic linear range for TNT from 10 to 2000 ng mL-1. The experiments demonstrate a low detection limit of 2.15 ng mL-1. The intra-day precisions for 25, 100 and 500 ng mL-1 were 4.6, 2.3 and 0.5% (RSD, n = 6), inter-day precisions for 25, 100 and 500 ng mL-1 were 4.2, 2.5 and 0.9% (RSD, n = 6), respectively. The developed sensor was validated with river water, dust, and soil samples, and the achieved spiked recoveries were immensely satisfied from 98.1% to 102.0%. The Fe@SiO2-NH2 possessed excellent reusability. This sensor exhibits that it is simple, sensitive and selective, and will be a vital analytical tool for TNT in many fields.
Asunto(s)
Nanoestructuras , Puntos Cuánticos , Trinitrotolueno , Carbono , Límite de Detección , Dióxido de SilicioRESUMEN
4-Carboxyphenylboronic acid was used as the single precursor to facilely prepare fluorescent carbon quantum dots by one-step solvothermal method. The as-obtained carbon dots (CDs) exhibited highly selective and sensitive for benzo[a]pyrene (BaP), and may be a splendid sensor for sensing BaP. The principle was that the as-prepared CDs could form a complex with BaP through hydrophobic interaction which causes the decrease of fluorescence intensity of CDs by static quenching principle. The constructed ï¬uorescent sensor exhibited excellent linearity ranged from 0.002 to 0.06 µg mL-1 and provided a low limit of detection of 0.16 ng mL-1. The experimental results showed that this ï¬uorescent sensor resulted in simplicity, rapidness, low cost, short analytical time, and high sensitivity and stability. Validation with real water samples endowed the sensor high reliability and feasibility for BaP determination in practical application in various samples.
Asunto(s)
Carbono , Puntos Cuánticos , Benzo(a)pireno , Fluorescencia , Colorantes Fluorescentes , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia , AguaRESUMEN
In present work, we reported a new nanomaterial nano Fe0 decorated with SiO2 and dopamine by self-assembly method (Fe@SiO2@PDA). A sensitive method for determination of Sudan pollutants in aqueous samples was developed using Fe@SiO2@PDA as magnetic solid phase extraction adsorbents prior to high-performance liquid chromatography with variable wavelength detector. The possible parameters which would affect the enrichment have been optimized. The best parameters were as follows: elutent, 4.5 mL methanol; adsorbent dosage, 30 mg; adsorption time, 20 min; elution time, 18 min; sample pH 7; sample volume, 40 mL. The experimental results demonstrated that Fe@SiO2@PDA exhibited good adsorption properties to Sudan Red dyes. The established method provided excellent linear ranges over 0.01-50 µg L-1 and detection limits ranged from 2.0 to 5.1 ng L-1 for Sudan red I-IV. The developed method was also evaluated with real water samples and the results demonstrated that it was of applicative value owing to its merits including robustness, easy operation, fastness, cheapness and high enrichment efficiency, and had great prospect in environmental fields.
Asunto(s)
Contaminantes Ambientales , Nanoestructuras , Contaminantes Químicos del Agua , Adsorción , Cromatografía Líquida de Alta Presión , Hierro , Fenómenos Magnéticos , Dióxido de Silicio , Extracción en Fase Sólida , Sudán , Contaminantes Químicos del Agua/análisisRESUMEN
Organochlorine pesticides (OCPs) have received much attention due to their toxicity. Reliable methods to monitor their residues in the environment are needed. Here, magnetic polyamidoamine dendrimers were prepared by co-precipitation, Michael addition, and amidation. The magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs-this feature was utilized to construct a sensitive tool for monitoring OCPs in water samples. The proposed method provided remarkable linearity from 0.1 to 500 µg/L and satisfactory limits of detection from 0.012 to 0.029 µg/L. The spiked recoveries of the four target analytes were 91.8%-103.5% with relative standard deviations less than 4.5%. The magnetic materials had good reusability. The results indicated that the resulting method was an efficient, easy, rapid, economical, and eco-friendly tool for monitoring OCPs in aqueous samples.
Asunto(s)
Dendrímeros , Hidrocarburos Clorados , Plaguicidas , Contaminantes Químicos del Agua , Cromatografía Líquida de Alta Presión , Hidrocarburos Clorados/análisis , Fenómenos Magnéticos , Plaguicidas/análisis , Poliaminas , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Sewage and sludge are usually treated separately. Considering improving sludge treatment while improving sewage treatment is beneficial to the synergetic effect of sewage treatment and sludge treatment. The efficiency of pulverized coal-activated sludge (PAS) on contaminant removal, sludge calorific value, and combustion characteristic was investigated in contrast to conventional activated sludge (CAS) using the laboratory-scale sequencing batch reactor (SBR). Results indicated that the average chemical oxygen demand, ammonium nitrogen, total nitrogen, and total phosphorus removal efficiency of PAS were highest under a dosage of 0.4 g/L, which were 98.56%, 94.22%, 68.60%, and 95.96%, respectively. The average effluent concentration satisfied the Level A discharge standard of pollutants for municipal wastewater treatment plants (GB18918-2002). The calorific value and maximum weight loss of PAS gradually increased adjusting the dosage of pulverized coal. At the pulverized coal dosage of 0.2 g/L, the calorific value of PAS with 70% water content is 3,824.07 kJ/kg, which can satisfy the requirement of self-maintained combustion. Overall, the pulverized coal can simultaneously improve the treatment of wastewater in SBR and promote the sludge combustion by increasing calorific value. Therefore, PAS system is an innovation based on improving the sewage treatment sludge combustion. PRACTITIONER POINTS: An innovative method to simultaneously improving wastewater treatment and sewage sludge combustion using pulverized coal-activated sludge was developed. The average COD, NH 4 + - N , TN, and TP removal efficiency of PAS-0.4 is best. The 70% moisture content sludge calorific values of 3,824.07 kJ/kg in PAS-0.2 can satisfy the requirement of self-maintained combustion.
Asunto(s)
Aguas del Alcantarillado , Purificación del Agua , Análisis de la Demanda Biológica de Oxígeno , Reactores Biológicos , Carbón Mineral/análisis , Nitrógeno , Fósforo , Eliminación de Residuos Líquidos , Aguas ResidualesRESUMEN
Genetic modification of industrial yeast strains often faces more difficulties than that of laboratory strains. Thus, new approaches are still required. In this research, the Angel Yeast-derived haploid strain Kα was genetically modified by multiple rounds of δ-integration, which was achieved via URA3 recycling. Three δ-integrative plasmids, pGδRU, pGδRU-BGL, and pGδRU-EG, were first constructed with two 167 bp δ sequences and a repeat-URA3-repeat fragment. Then, the δ-integrative strains containing the bgl1 or egl2 gene were successfully obtained by one-time transformation of the linearized pGδRU-BGL or pGδRU-EG fragment, respectively. Their counterparts in which the URA3 gene was looped out were also easily isolated by selection for growth on 5´-fluoroorotic acid plates, although the ratio of colonies lacking URA3 to the total number of colonies decreased with increasing copy number of the corresponding integrated cellulase-encoding gene. Similar results were observed during the second round of δ-integration, in which the δ-integration strain Kα(δ::bgl1-repeat) obtained from the first round was transformed with a linearized pGδRU-EG fragment. After 10 rounds of cell growth and transfer to fresh medium, the doubling times and enzyme activities of Kα(δ::bgl1-repeat), Kα(δ::egl2-repeat), and Kα(δ::bgl1-repeat)(δ::egl2-repeat) showed no significant change and were stable. Further, their maximum ethanol concentrations during simultaneous saccharification and fermentation of pretreated corncob over a 7-day period were 46.35, 33.13, and 51.77 g/L, respectively, which were all substantially higher than the parent Kα strain. Thus, repetitive δ-integration with URA3 recycling can be a feasible and valuable method for genetic engineering of Angel Yeast. These results also provide clues about some important issues related to δ-integration, such as the structural stability of δ-integrated genes and the effects of individual integration-site locations on gene expression. Further be elucidation of these issues should help to fully realize the potential of δ-integration-based methods in industrial yeast breeding.
Asunto(s)
Celulasa/genética , Cromosomas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Celulasa/metabolismo , Cromosomas/metabolismo , Ingeniería Genética , Conformación Proteica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Polyamidoamine dendrimer decorated Fe3O4 magnetic nanoparticles was synthesized and grafted with 4-mercaptobenzoic acid (4-MBA). The resulting material was utilized to develop an effective magnetic solid phase extraction method in combination with high performance liquid chromatography for trace determination of polycyclic aromatic hydrocarbons including phenanthrene (PHE), anthracene (ANT), fluoranthene (FLT), pyrene (PYR) and benzo(a)pyrene (BaP). The MNPs@G3.0@4-MBA exhibited to be an efficient extracting medium due to the existence of terminal benzene ring groups, the internal pores, and strong hydrophobic interactions and π-π interactions. The experiments demonstrated that the proposed method possessed excellent linearity in the concentration range of 0.1-300 µg L-1 with correlation coefficients (R) larger than 0.997, and the limits of detection (LODs, S/N = 3) according to the ratio of signal to noise equal to three of PHE, ANT, FLT, PYR and BaP were 0.014 µg L-1, 0.032 µg L-1, 0.055 µg L-1, 0.027 µg L-1 and 0.039 µg L-1, respectively. The proposed method was applied to real water samples and the spiked recoveries were over the range of 92-99%. The results showed that the method earned good repeatability and high sensitivity, and the as-prepared materials were stable and reusable, which displayed that the proposed method would have a wonderful application prospect.
RESUMEN
BACKGROUND: Pediatric obstructive sleep apnea/hypopnea syndrome (OSAHS) is a multifactorial syndrome caused by many risk factors, such as craniofacial anomalies, adenotonsillar hypertrophy, obesity, and airway inflammation. Although new treatment patterns have recently been proposed, treatment methods for children remain particularly challenging and controversial. This randomized controlled trial was designed to investigate the efficacy of adenotonsillectomy and/or orthodontic treatment for children who have mild OSAHS with mandibular retrognathia. METHODS: A sample of 352 children with mild OSAHS and mandibular retrognathia, who are aged between 7 and 10 years, will be enrolled in the study. They will be randomized into four groups: the drug treatment group, the surgical treatment group, the orthodontic treatment group, or the surgery and postoperative orthodontic group. After randomization the children will receive treatments within 4 weeks. Outcome assessment will take place at the following points: (1) baseline, (2) 7 months after the treatment starting point, (3) 12 months after the treatment starting point, and (4) 24 months after the treatment starting point. The primary endpoint of the trial is the mean change in obstructive apnea/hypopnea index. Other endpoints will consist of the lowest oxygen saturation, apnea index, and hypopnea index assessed by polysomnography, subjective symptoms (assessed by the OSA-20 questionnaire), cephalometric measurements, and morphologic analysis of the upper airway. DISCUSSION: The results of this study will provide valuable evidence for the merits and long-term efficacy of different treatment approaches and contribute to facilitating the multidisciplinary treatment of pediatric OSAHS. TRIAL REGISTRATION: ClinicalTrials.gov : NCT03451318. Registered on 2 March 2018 (last update posted 19 April 2018).