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1.
Angew Chem Int Ed Engl ; 62(37): e202305661, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37479952

RESUMEN

The low-temperature reverse water-gas shift (RWGS) reaction faces the following obstacles: low activity and unsatisfactory selectivity. Herein, the dual-active sites of platinum (Pt) clusters and frustrated Lewis pair (FLP) on porous CeO2 nanorods (Ptcluster /PN-CeO2 ) provide an interface-independent pathway to boost high performance RWGS reaction at low temperatures. Mechanistic investigations illustrate that Pt clusters can effectively activate and dissociate H2 . The FLP sites, instead of the metal and support interfaces, not only enhance the strong adsorption and activation of CO2 , but also significantly weaken CO adsorption on FLP to facilitate CO release and suppress the CH4 formation. With the help of hydrogen spillover from Pt to PN-CeO2 , the Ptcluster /PN-CeO2 catalysts achieved a CO yield of 29.6 %, which is very close to the thermodynamic equilibrium yield of CO (29.8 %) at 350 °C. Meanwhile, the Ptcluster /PN-CeO2 catalysts delivered a large turnover frequency of 8720 h-1 . Moreover, Ptcluster /PN-CeO2 operated stably and continuously for at least 840 h. This finding provides a promising path toward optimizing the RWGS reaction.

2.
Chirality ; 34(9): 1209-1218, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35678370

RESUMEN

Metal organic frameworks (MOFs) have drawn broad attention as a novel stationary phase due to their highly porous structure, modifiable pores, large specific surface areas, and satisfactory stability. In this paper, histidine-zeolitic imidazolate framework-8 (His-ZIF-8) synthesized at room temperature was physically coated to the internal surface of the capillary column and the carboxymethyl-ß-cyclodextrin (CM-ß-CD) as the chiral selector was chemically bonded to the His-ZIF-8@capillary column. The prepared CM-ß-CD@His-ZIF-8@capillary column was used for the enantioseparation of amlodipine, propranolol, and atenolol in capillary electrochromatography. In contrast to the CM-ß-CD@capillary column without His-ZIF-8, the CM-ß-CD@His-ZIF-8@capillary column reveals significantly improved enantiodiscrimination performance for amlodipine (Rs : 0 → 2.29), propranolol (Rs : 0 → 1.69), and atenolol (Rs : 0 → 0.79). His-ZIF-8 concentration, buffer pH, buffer concentration, and the proportion of organic modifier were evaluated in detail with enantiomerically separating chiral molecules. The repeatability of intraday, day-to-day, and column-to-column have been discussed; the result was preferable, and the relative standard deviation (RSD) of separation parameters was <6.7%.


Asunto(s)
Electrocromatografía Capilar , Zeolitas , Amlodipino/análisis , Atenolol , Electrocromatografía Capilar/métodos , Histidina , Propranolol , Estereoisomerismo , beta-Ciclodextrinas
3.
Prenat Diagn ; 41(9): 1080-1088, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33720417

RESUMEN

OBJECTIVE: Twin-twin transfusion syndrome (TTTS) causes perinatal mortality and morbidity in monochorionic twins. The early recognition of and interventional therapy for TTTS is associated with a more favorable overall prognosis. However, the prediction by the use of ultrasound in the first trimester has relatively poor sensitivity and specificity. This study aimed to identify metabolic biomarkers to aid in ultrasound screening of TTTS. METHODS: Maternal plasma was prospectively collected between 11 and 15 weeks of gestation in apparently uncomplicated monochorionic-diamniotic twin pregnancies. This cohort was divided into: (i) patients who were subsequently diagnosed with TTTS by using ultrasound; (ii) uncomplicated matched controls. Metabolome was profiled by using gas chromatography-mass spectrometry. RESULTS: The levels of fatty acids, organic acids, oxaloacetic acid, and beta-alanine were significantly lower in the TTTS maternal plasma at 11-15 weeks of gestation, and methionine and glycine were also higher (p < 0.05, FDR<0.12). Generally, in TTTS pregnancies, the metabolisms of amino acid, carbohydrate, cofactors, vitamins, and purine were "down-regulated"; whereas bile secretion and pyrimidine metabolism were "upregulated." CONCLUSIONS: The metabolomics scanning of early gestation maternal plasma may identify those pregnancies that subsequently develop TTTS; in particular, downregulated fatty acid levels may be biologically plausible to be implicated in the pathogenesis of TTTS.


Asunto(s)
Transfusión Feto-Fetal/complicaciones , Metaboloma/fisiología , Plasma/metabolismo , Adulto , China , Femenino , Transfusión Feto-Fetal/metabolismo , Edad Gestacional , Humanos , Estudios Longitudinales , Proyectos Piloto , Embarazo , Complicaciones del Embarazo/terapia , Estudios en Gemelos como Asunto
4.
BMC Med Inform Decis Mak ; 21(Suppl 2): 89, 2021 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-34330249

RESUMEN

BACKGROUND: Semantic segmentation of white matter hyperintensities related to focal cerebral ischemia (FCI) and lacunar infarction (LACI) is of significant importance for the automatic screening of tiny cerebral lesions and early prevention of LACI. However, existing studies on brain magnetic resonance imaging lesion segmentation focus on large lesions with obvious features, such as glioma and acute cerebral infarction. Owing to the multi-model tiny lesion areas of FCI and LACI, reliable and precise segmentation and/or detection of these lesion areas is still a significant challenge task. METHODS: We propose a novel segmentation correction algorithm for estimating the lesion areas via segmentation and correction processes, in which we design two sub-models simultaneously: a segmentation network and a correction network. The segmentation network was first used to extract and segment diseased areas on T2 fluid-attenuated inversion recovery (FLAIR) images. Consequently, the correction network was used to classify these areas at the corresponding locations on T1 FLAIR images to distinguish between FCI and LACI. Finally, the results of the correction network were used to correct the segmentation results and achieve segmentation and recognition of the lesion areas. RESULTS: In our experiment on magnetic resonance images of 113 clinical patients, our method achieved a precision of 91.76% for detection and 92.89% for classification, indicating a powerful method to distinguish between small lesions, such as FCI and LACI. CONCLUSIONS: Overall, we developed a complete method for segmentation and detection of WMHs related to FCI and LACI. The experimental results show that it has potential clinical application potential. In the future, we will collect more clinical data and test more types of tiny lesions at the same time.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular , Algoritmos , Humanos , Imagen por Resonancia Magnética , Semántica
5.
Mikrochim Acta ; 188(6): 186, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33978843

RESUMEN

Metal-organic framework (UiO-66-NH2)-incorporated organic polymer monolith was prepared by thermal polymerization. By virtue of the superior physical and chemical properties, the UiO-66-NH2-modified organic monolith was then functionalized by chiral selector cellulase via the condensation reaction between the primary amino groups and aldehyde groups. The synthesized materials were characterized by Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectrometry, thermogravimetric analysis, and nitrogen sorption isotherm. The cellulase@poly(glycidyl methacrylate-UiO-66-NH2-ethylene glycol dimethacrylate) (cellulase@poly(GMA-UiO-66-NH2-EDMA)) monolith was applied to enantiomerically separate the basic racemic forms of metoprolol, atenolol, esmolol, bisoprolol, and propranolol. In contrast to the cellulase@poly(GMA-co-EDMA) monolith without UiO-66-NH2, the cellulase@poly(GMA-UiO-66-NH2-EDMA) monolith reveals significantly improved enantiodiscrimination performance for metoprolol (Rs: 0 → 1.67), atenolol (Rs: 0 → 1.50), esmolol (Rs: 0 → 1.52), bisoprolol (Rs: 0 → 0.36), and propranolol (Rs: 0 → 0.44). The immobilization pH of cellulase, buffer pH, UiO-66-NH2 concentration, and the proportion of organic modifier were evaluated in detail with enantiomerically separating chiral molecules. The intra-day, inter-day, column-to-column, and inter-batch precision have been discussed, the result was preferable, and the relative standard deviation (RSD) of separation parameters was <4.3%. Schematic representation of the preparation of a UiO-66-NH2-modified organic polymer monolith for enantioseparating five racemic ß-blockers. UiO-66-NH2 was synthesized and converted into a monolith as the stationary phase. Then, the modified monolith containing cellulase as the chiral selector was applied in a capillary electrochromatography system for enantioseparating chiral drugs.


Asunto(s)
Antagonistas de Receptores Adrenérgicos beta 1/aislamiento & purificación , Celulasa/química , Enzimas Inmovilizadas/química , Estructuras Metalorgánicas/química , Fenoxipropanolaminas/aislamiento & purificación , Antagonistas de Receptores Adrenérgicos beta 1/química , Electrocromatografía Capilar , Hypocreales/enzimología , Metacrilatos/química , Fenoxipropanolaminas/química , Ácidos Polimetacrílicos/química , Estereoisomerismo , Circonio/química
6.
J Environ Manage ; 297: 113430, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34351299

RESUMEN

The growing number of industrial carbon emissions have resulted in a significant increase in the greenhouse gas carbon dioxide (CO2), which, in turn, will have a major impact on climate change. Therefore, the reduction, storage, and reuse of CO2 is an important concern in modern society. Calcium oxide (CaO) is known to be an excellent adsorbent of CO2 in a high-temperature environment. However, since deterioration of the adsorbent is likely to occur after repeated cycles of adsorption under high temperature conditions, it would be desirable to mitigate this phenomenon, in order to maintain the stability of CaO. In the present study, common eggshell waste was used as the starting material. The main component of eggshell waste is calcium carbonate (CaCO3), which was purified to produce CaO. Different surfactants and amino-containing polymers were added to synthesize CaO-based adsorbents with different configurations and pore sizes. The amount of CO2 adsorbed was determined using a thermogravimetric analyzer (TGA). The results showed that the CO2 adsorption capacity of the synthetic CaO recovered from purified eggshell waste could reach 0.6 g-CO2/g-sorbent, indicating a good adsorption capacity. CaO modified with a dopamine-containing polymer was shown to have an adsorption capacity of 0.62 g-CO2/g-sorbent. Moreover, it showed an excellent adsorption capacity of 0.40 g-CO2/g-sorbent, even after 10 cycles of CO2 adsorption. The present study suggests that using eggshell waste to synthesize CaO-based adsorbents for effective CO2 adsorption can not only reduce environmental waste, but also have the potential to capture greenhouse gas CO2 emissions, which conforms to the principles of green chemistry.


Asunto(s)
Dióxido de Carbono , Gases de Efecto Invernadero , Adsorción , Animales , Compuestos de Calcio , Cáscara de Huevo , Óxidos
7.
Turk J Med Sci ; 51(3): 1021-1026, 2021 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-33237658

RESUMEN

Background/aim: Analysis of the characteristics of influenza virus in imported cases in Guangxi province of China. Materials and methods: Throat swabs of imported cases with influenza-like symptoms were detected by real-time PCR from July 2016 to December 2019. Results: 1292 laboratory detections of influenza were reported in 3974 influenza-like cases, of which 71.67% (926) were influenza A. The ratio of test positive was 32.82%. The proportion of detections of influenza B was 28.33% (366). A total of 70.51% of the cases mostly came from Vietnam (911). A total of 86.76% (1121) of the cases were imported from Dongxing Port, Nanning Airport, and Pingxiang Port. There was no statistical difference in all age groups. At the same time, 3 of the untyped A-type specimens were sequenced by next- generation sequencing. Among them, the sequences of 2 specimens from Vietnam had high homology with the influenza strain H3N2 in Hong Kong in 2017. The specimen sequence from Thailand is highly homologous to the influenza pandemic strain H1N1 in Brisbane, Australia in 2018. Conclusion: Imported influenza cases in Guangxi have occurred throughout the year, with higher numbers in winter and spring. The cases mostly came from Vietnam with influenza A. Relevant measures should be taken to control the further spread of the virus.


Asunto(s)
Brotes de Enfermedades , Virus de la Influenza A , Virus de la Influenza B , Gripe Humana/epidemiología , Estaciones del Año , Viaje , Adolescente , Adulto , China , Brotes de Enfermedades/prevención & control , Epidemias , Humanos , Subtipo H1N1 del Virus de la Influenza A , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana/etiología , Gripe Humana/transmisión , Gripe Humana/virología , Persona de Mediana Edad , Adulto Joven
8.
J Am Chem Soc ; 142(29): 12643-12650, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32584563

RESUMEN

The controllable synthesis of stable single-metal site catalysts with an expected coordination environment for high catalytic activity and selectivity is still challenging. Here, we propose a cation-exchange strategy for precise production of an edge-rich sulfur (S) and nitrogen (N) dual-decorated single-metal (M) site catalysts (M = Cu, Pt, Pd, etc.) library. Our strategy relies on the anionic frameworks of sulfides and N-rich polymer shell to generate abundant S and N defects during high-temperature annealing, further facilitating the stabilization of exchanged metal species with atomic dispersion and excellent accessibility. This process was traced by in situ transmission electron microscopy, during which no metal aggregates were observed. Both experiments and theoretical results reveal the precisely obtained S, N dual-decorated Cu sites exhibit a high activity and low reaction energy barrier in catalytic hydroxylation of benzene at room temperature. These findings provide a route to controllably produce stable single-metal site catalysts and an engineering approach for regulating the central metal to improve catalytic performance.

9.
Nutr J ; 19(1): 13, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-32039726

RESUMEN

BACKGROUND: Gestational diabetes mellitus (GDM) is correlated with an increased risk of adverse perinatal outcomes for both the mother and offspring. Previous research has reported correlations between maternal dietary patterns and GDM, but such evidence for twin pregnancies is lacking. This study aimed to identify maternal dietary patterns in the second trimester and investigate their relationships with the risk of GDM among women who were pregnant with twins in China. METHODS: A longitudinal twin pregnancies birth cohort study of women who were pregnant with twins in China was conducted. Maternal dietary intake in the second trimester was recorded by using a food frequency questionnaire prior to the diagnosis of GDM among participants from the prospective twin pregnancies birth cohort in Chongqing City. GDM was diagnosed with a 75 g 2-h oral glucose tolerance test at 23-26 weeks of gestation. Dietary patterns were identified by principal components analysis, and the correlations between dietary pattern and GDM were examined using multivariable logistic regression analyses. RESULTS: Of the 324 participants, 101 (31.2%) were diagnosed with GDM. Four dietary patterns were identified: a vegetable-based pattern, a poultry-and-fruit-based pattern, a sweet-based pattern and a plant-protein-based pattern. Multivariate analysis showed that none of the dietary patterns were correlated with the risk of GDM among women who were pregnant with twins, but the sweet-based dietary pattern, which was associated with a higher GDM risk for quartile 4 versus quartile 1 (OR 2.69; 95% CI: 1.09, 6.66) among non-overweight women (prepregnancy BMI < 24.0). CONCLUSION: Dietary patterns were not correlated with later GDM risk among women who were pregnant with twins in western China, whereas a high intake of sweets was associated with a higher risk for GDM among women who were not overweight prior to pregnancy. TRIAL REGISTRATION: ChiCTR-OOC-16008203. Retrospectively registered on 1 April 2016.


Asunto(s)
Diabetes Gestacional/epidemiología , Dieta/métodos , Azúcares de la Dieta/efectos adversos , Madres , Segundo Trimestre del Embarazo , Embarazo Gemelar , Adulto , China/epidemiología , Estudios de Cohortes , Dieta/efectos adversos , Dieta/estadística & datos numéricos , Azúcares de la Dieta/administración & dosificación , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Estudios Longitudinales , Embarazo , Análisis de Componente Principal , Encuestas y Cuestionarios
10.
Mikrochim Acta ; 187(7): 385, 2020 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-32533434

RESUMEN

A ß-Cyclodextrin covalent organic framework (ß-CD COF) was successfully prepared under ambient temperature with a mild chemistry strategy from heptakis(6-amino-6-deoxy)-ß-cyclodextrin and terephthalaldehyde. It was embedded into the poly[(glycidyl methacrylate)-co-(ethylene dimethacrylate)] [poly(GMA-co-EDMA)] monolith and served as the ß-CD COF material-incorporated monolith. The synthetic materials were characterized by field emission scanning electron microscopy, energy-dispersive X-ray mapping analysis, transmission electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, and N2 adsorption-desorption isotherm. The ß-CD COF material-incorporated monolith achieved baseline separation in capillary electrochromatographic separation of three amides, three amino acids, three nucleosides, four aromatic acids, and three positional isomers (with resolution values of three amides, 1.75 and 1.54; three amino acids, 5.24 and 1.75; three nucleosides, 2.56 and 1.77; four aromatic acids, 6.96, 2.74, and 1.64; three positional isomers, 1.61 and 1.50). In comparison with the original monolith, the ß-CD COF material-incorporated monolith shows significantly enhanced resolution for mixed molecules. The effect of pH and concentration of buffer and applied voltage were discussed in detail. The fabricated monolith showed good stability and reproducibility (relative standard deviation (RSD) < 6.9%). Molecular modeling illuminated the interactions between the small molecules and stationary phase, and provided a sufficient theoretical basis for experimental data. Graphical abstract Schematic presentation of the preparation of ß-cyclodextrin covalent organic framework (ß-CD COF) material-incorporated organic polymer monolith for separating the amides, amino acids, nucleosides, aromatic acids, and positional isomers. ß-CD COF materials were synthesized and incorporated into the monolith as the stationary phase. Then, the incorporated monolith was applied in the capillary electrochromatography system for separating small molecules.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3275-80, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26978948

RESUMEN

A method for determination of beryllium in soils and sediments by microwave-acid digestion/graphite furnace atomic absorption (GFAA) is described. In this paper, the working conditions of the instrument are optimized, the drawing of calibration curve is expounded, the pretreatment process of soil and sediments (including microwave heating process and the selection of digestion system) is discussed, and the interference of coexisting elements is examined. The sample was pretreated by microwave digestion parameters using HNO3/ HCl/HF mixed acid system. The method is fast and simple without matrix modifier, and has no interference by coexisting ions, and has high repeatability and reproducibility. Under the optimal experimental conditions, the limit of detection (LOD) is 0.004 9 mg · kg⁻¹ (sample quantity 0.200 0 g, sample volume 25 mL), and the limits of quantitation (LOQ) is 0.20 mg · kg⁻¹. This method is used to measure the standard samples and actual samples, whether in the laboratory, or between laboratories, has good accuracy and precision.

12.
Int J Mol Sci ; 15(10): 19253-64, 2014 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-25342320

RESUMEN

DNA damage-regulated autophagy modulator protein 1 (DRAM1), a multi-pass membrane lysosomal protein, is reportedly a tumor protein p53 (TP53) target gene involved in autophagy. During cerebral ischemia/reperfusion (I/R) injury, DRAM1 protein expression is increased, and autophagy is activated. However, the functional significance of DRAM1 and the relationship between DRAM1 and autophagy in brain I/R remains uncertain. The aim of this study is to investigate whether DRAM1 mediates autophagy activation in cerebral I/R injury and to explore its possible effects and mechanisms. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R) Neuro-2a cell model to mimic cerebral I/R conditions in vitro, and RNA interference is used to knock down DRAM1 expression in this model. Cell viability assay is performed using the LIVE/DEAD viability/cytotoxicity kit. Cell phenotypic changes are analyzed through Western blot assays. Autophagy flux is monitored through the tandem red fluorescent protein-Green fluorescent protein-microtubule associated protein 1 light chain 3 (RFP-GFP-LC3) construct. The expression levels of DRAM1 and microtubule associated protein 1 light chain 3II/I (LC3II/I) are strongly up-regulated in Neuro-2a cells after OGD/R treatment and peaked at the 12 h reperfusion time point. The autophagy-specific inhibitor 3-Methyladenine (3-MA) inhibits the expression of DRAM1 and LC3II/I and exacerbates OGD/R-induced cell injury. Furthermore, DRAM1 knockdown aggravates OGD/R-induced cell injury and significantly blocks autophagy through decreasing autophagosome-lysosome fusion. In conclusion, our data demonstrate that DRAM1 knockdown in Neuro-2a cells inhibits autophagy by blocking autophagosome-lysosome fusion and exacerbated OGD/R-induced cell injury. Thus, DRAM1 might constitute a new therapeutic target for I/R diseases.


Asunto(s)
Autofagia/fisiología , Isquemia Encefálica/metabolismo , Glucosa/metabolismo , Proteínas de la Membrana/metabolismo , Neuroblastoma/metabolismo , Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Adenina/análogos & derivados , Adenina/farmacología , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Regulación hacia Arriba/efectos de los fármacos
13.
Heliyon ; 10(10): e30990, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38813192

RESUMEN

Currently, the development of HRESs (hybrid renewable energy systems) in remote areas is of great importance and popularity. However, measuring and optimizing the capacity of these systems faces a difficult challenge. Multiple works had been reported in the literature to optimize such systems, all of which aim to achieve an optimal configuration with minimum annual net cost. Therefore, the significance of providing off-grid electrification to remote areas through HRESs can be highlighted as a crucial case for sustainable growth. Accordingly, the study proposes a modified metaheuristic approach, known as the Hybrid Golden Search Algorithm (HGSA), for long-term application planning and optimization of the off-grid HRES. The aim of this algorithm is to minimize the amount of net cost which is used annually; to reduce the probability of power supply interruption. In order to assess the effectiveness of the proposed algorithm, a simulation study over a long period on a remote area was conducted. From the results, increasing the reliability level from 1 % to 3 % causes a decrease in the total net annual cost by around 7.3 % under the proposed HGSA and also results in a reduction in component size (around 6 % and 21 % reductions for the wind turbine area and storage tanks, respectively). Further, the HGSA technique obtains the lowest value of fitness function for the hybrid system at a reliability level of 3 %, which is 31,539,810$. This result demonstrates that the efficiency of HGSA outperforms Fuzzy Logic and Optimization, Artificial Bee Colony (ABC), and GSA techniques. Based on this, the proposed HGSA could lead to more promising results than the other comparative algorithms. Hence, the proposed HGSA can be a valuable tool for long-term application planning and optimization of off-grid HRES, which can contribute significantly to achieving sustainable development goals.

14.
Toxics ; 12(3)2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38535904

RESUMEN

Various studies have shown that the heavy use of pharmaceuticals poses serious ecological risks, especially in metropolitan areas with intensive human activities. In this study, the spatial distribution, sources, and ecological risks of 29 pharmaceuticals in 82 surface waters collected from the North Canal Basin in Beijing were studied. The results showed that the pharmaceutical concentrations ranged from not detected to 193 ng/L, with ampicillin being undetected while ofloxacin had a 100% detection frequency, which indicates the widespread occurrence of pharmaceutical pollution in the North Canal Basin. In comparison with other freshwater study areas, concentrations of pharmaceuticals in the North Canal Basin were generally at moderate levels. It was found that pharmaceutical concentrations were always higher in rivers that directly received wastewater effluents. Source analysis was conducted using the positive matrix factorization model. Combining the spatial pollution patterns of pharmaceuticals, it has been found that wastewater effluents contributed the most to the loads of pharmaceuticals in the studied basin, while in suburban areas, a possible contribution of untreated wastewater was demonstrated. Risk assessment indicated that approximately 55% of the pharmaceuticals posed low-to-high ecological risks, and combining the results of risk analyses, it is advised that controlling WWTP effluent is probably the most cost-effective measure in treating pharmaceutical pollution.

15.
Huan Jing Ke Xue ; 45(3): 1760-1768, 2024 Mar 08.
Artículo en Zh | MEDLINE | ID: mdl-38471887

RESUMEN

In order to explore the status of soil heavy metal pollution and environmental quality in west Hunan, relevant areas of Phoenix County were selected as the study area. Using data from 440 soil samples collected in the study area from June to August 2022, the pH value of the soil and contents of eight heavy metal elements, namely, As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, were analyzed. The PMF model was used for traceability analysis and geochemical evaluation of soil environmental quality. The results showed that the average values of soil heavy metals ω(Zn), ω(Cr), ω(Pb), ω(Ni), ω(Cu), ω(As), ω(Cd), and ω(Hg) were 81.02, 64.67, 31.63, 29.27, 25.52, 9.93, 0.28, and 0.13 mg·kg-1, respectively. The soil in the study area was mainly weakly acidic, and the contents of the Cd and Hg elements were relatively high compared to the national soil background values and were highly variable. The contents of the Hg and Cd elements in forest land were higher than that in other land uses. The PMF model results showed that the contribution rates of heavy metal pollution sources in the study area were mining sources (37.4%), atmospheric sedimentation sources (7.7%), natural sources (41.1%), and agricultural activity sources (13.8%) and provided suggestions on pollution control measures according to the spatial distribution of the four types of pollution sources. Through the comprehensive assessment of soil environmental geochemistry, the study area was divided into three types of plots, namely, non-risk areas (94.27 km2), accounting for 76.38%; risk-controllable areas (27.45 km2), accounting for 22.24%; and high-risk areas (1.7 km2), accounting for 1.38%. This study provided data support for the prevention and control measures of land pollution in the research area, as well as the delineation of the prevention and control scope.

16.
Reprod Sci ; 31(5): 1290-1302, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38151653

RESUMEN

Dysfunction of extravillous trophoblasts (EVTs) might cause early pregnancy failure by interfering with embryo implantation and/or placentation. We previously reported that the villus miR-3074-5p expression level was increased, whereas the peripheral level of GDF15, a predict target gene of miR-3074-5p, was decreased in recurrent miscarriages (RM) patients, and miR-3074-5p could enhance apoptosis but reduce invasion of human extravillous trophoblast cells (EVTs). The aim of this study was to further explore roles of miR-3074-5p/GDF15 pathway in regulation of EVTs function. It was validated that GDF15 was not the direct target of miR-3074-5p, whereas EIF2S1, an upstream regulator of GDF15 maturation and secretion, was the direct target of miR-3074-5p. The villus expression levels of GDF15 and EIF2S1 were significantly decreased in RM patients. Knockdown of GDF15 expression presented inhibitory effects on proliferation, migration, and invasion of HTR8/SVneo cells. Up-regulated miR-3074-5p expression led to the significant decreased GDF15 expression in HTR8/SVneo cells, and this effect could be efficiently reversed by the overexpression of EIF2S1. Meanwhile, the suppressive effects of miR-3074-5p on proliferation, migration, and invasion of HTR8/SVneo cells could be intercepted by the treatment of recombinant human GDF15 protein. Collectively, these data suggested that miR-3074-5p could reduce GDF15 production via targeting inhibition of EIF2S1 expression, and the deficiency in GDF15 function might lead to the early pregnancy loss by attenuating proliferation and invasion of EVTs.


Asunto(s)
Aborto Habitual , Factor 2 Eucariótico de Iniciación , Factor 15 de Diferenciación de Crecimiento , MicroARNs , Trofoblastos , Humanos , Trofoblastos/metabolismo , Factor 15 de Diferenciación de Crecimiento/metabolismo , Factor 15 de Diferenciación de Crecimiento/genética , Aborto Habitual/metabolismo , Aborto Habitual/genética , Femenino , MicroARNs/metabolismo , MicroARNs/genética , Embarazo , Factor 2 Eucariótico de Iniciación/metabolismo , Transducción de Señal , Proliferación Celular , Movimiento Celular , Línea Celular , Adulto
17.
Breast Cancer ; 31(4): 726-734, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705942

RESUMEN

BACKGROUND: Simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) is an innovative technique delivering a higher dose to the tumor bed while irradiating the entire breast. This study aims to assess the clinical outcomes, adverse effects, and cosmetic results of SIB-IMRT following breast-conserving surgery in breast cancer patients. METHODS: We conducted a retrospective analysis of 308 patients with stage 0-III breast cancer who underwent breast-conserving surgery and SIB-IMRT from January 2016 to December 2020. The prescribed doses included 1.85 Gy/27 fractions to the whole breast and 2.22 Gy/27 fractions or 2.20 Gy/27 fractions to the tumor bed. Primary endpoints included overall survival (OS), local-regional control (LRC), distant metastasis-free survival (DMFS), acute and late toxicities, and cosmetic outcomes. RESULTS: The median follow-up time was 36 months. The 3-year OS, LRC, and DMFS rates were 100%, 99.6%, and 99.2%, respectively. Five patients (1.8%) experienced local recurrence or distant metastasis, and one patient succumbed to distant metastasis. The most common acute toxicity was grade 1-2 skin reactions (91.6%). The most common late toxicity was grade 0-1 skin and subcutaneous tissue reactions (96.7%). Five patients (1.8%) developed grade 1-2 upper limb lymphedema, and three patients (1.1%) had grade 1 radiation pneumonitis. Among the 262 patients evaluated for cosmetic outcomes at least 2 years post-radiotherapy, 96.9% achieved excellent or good results, while 3.1% had fair or poor outcomes. CONCLUSIONS: SIB-IMRT after breast-conserving surgery in breast cancer patients demonstrated excellent clinical efficacy, mild acute and late toxicities, and satisfactory cosmetic outcomes in our study. SIB-IMRT appears to be a feasible and effective option for breast cancer patients suitable for breast-conserving surgery.


Asunto(s)
Neoplasias de la Mama , Mastectomía Segmentaria , Radioterapia de Intensidad Modulada , Humanos , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/mortalidad , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Anciano , Adulto , Radioterapia Adyuvante/métodos , Radioterapia Adyuvante/efectos adversos , Resultado del Tratamiento , Recurrencia Local de Neoplasia , Estudios de Seguimiento
18.
Nanomaterials (Basel) ; 13(2)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36677986

RESUMEN

The ultrafast water permeation property of graphene nanoplatelets (GNPs) synergically enhances the evaporation and water circulation processes in a micro heat pipe (MHP). An MHP is a promising phase-change heat-transfer device capable of transferring large amounts of heat energy efficiently. The hydrophobic, atomically smooth carbon walls of GNPs nanostructures provide a network of nanocapillaries that allows water molecules to intercalate frictionlessly among the graphene layers. Together with the attraction force of the oxygenated functional groups, a series of hydrophobic and hydrophilic surfaces are formed that significantly improve the water circulation rate. The intercalation of water molecules encourages the formation of water-thin film for film-wise evaporation. The effect of nano-wick thickness on the thermal performance of the MHP is investigated. A thinner GNP nano-wick is more favorable to film-wise evaporation while a thicker nano-wick promotes a higher water circulation rate from the condenser to the evaporator, leading to the existence of an optimal thickness. By benchmarking with the uncoated MHP, the thermal conductance of an MHP with a 46.9-µm GNP nano-wick manifests a maximum enhancement of 128%. This study provides insights on the feasible implementation of GNP nano-wicks into a highly efficient micro-scale electronics cooling device for environmental sustainability.

19.
J Chromatogr Sci ; 61(7): 699-704, 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35397163

RESUMEN

How to improve the enantiomer separation efficiency of drugs is a hot topic. In this paper, polydopamine (PDA) coating doped with graphene oxide (GO) by physical adsorption was used to modify the capillary column to enhance the enantioseparation efficiency of the drugs. In the capillary electrochromatography (CEC) system, the novel capillary column with carboxymethyl-ß-cyclodextrin (CM-ß-CD) as a chiral selector has completed the enantioseparation of four basic drugs (propranolol, metoprolol, amlodipine and chlorpheniramine). The optimum separation conditions were obtained by optimizing the pH of the buffer, the concentration of organic modifier, the concentration of the chiral selector and the voltage, and the resolution and peak shape were significantly improved compared with uncoated bare-fused column. The stability and reproducibility of the new capillary column were satisfactory and the relative standard deviation of intra-day and inter-day was <3.2%, and of column-to-column was <4.8%. The rich functional groups of GO are key factors to improve the enantioseparation efficiency, which also indicates that nanomaterials with easy modification of functional groups and large specific surface area are excellent resources for capillary modification applications.

20.
Artículo en Inglés | MEDLINE | ID: mdl-35635939

RESUMEN

Metal-organic frameworks (MOFs), defined as a class of microporous hybrid materials, are established by coordination of metal cations with functional organic ligands. In addition to outstanding porosity and large surface area, the structures and functions of MOFs can be designed and adjusted based on different destinations, which would be employed as stationary phases in various chromatographic modes. Pepsin, a class of protein, has been investigated as chiral selector owing to their unique interactions with analytes based on chiral or affinity selectivity. In this work, MOF-5 was exploited to grow on the support of poly (glycidyl methacrylate)-co-(ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths by layer-by-layer self-assembly method. Pepsin was subsequently bonded with the carboxyl group of MOF-5 through amidation reaction. The ultimate pepsin@MOF-5@poly(GMA-co-EDMA) column was applied for enantioseparation of six basic chiral drugs by capillary electrochromatography with good resolution and repeatability. Compared with the pepsin modified monolithic column, the newly prepared column with MOF-5 shows significantly enhanced enantiomeric resolution, which reveals that MOFs-modified capillary monolithic columns lead a promising road to separation of racemates by chromatography.


Asunto(s)
Electrocromatografía Capilar , Estructuras Metalorgánicas , Electrocromatografía Capilar/métodos , Estructuras Metalorgánicas/química , Pepsina A , Porosidad , Estereoisomerismo
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