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1.
Environ Sci Technol ; 58(28): 12664-12673, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38953777

RESUMEN

Investigating the fate of persistent organic pollutants in water distribution systems (WDSs) is of great significance for preventing human health risks. The role of iron corrosion scales in the migration and transformation of organics in such systems remains unclear. Herein, we determined that hydroxyl (•OH), chlorine, and chlorine oxide radicals are generated by Fenton-like reactions due to the coexistence of oxygen vacancy-related Fe(II) on goethite (a major constituent of iron corrosion scales) and hypochlorous acid (HClO, the main reactive chlorine species of residual chlorine at pH ∼ 7.0). •OH contributed mostly to the decomposition of atrazine (ATZ, model compound) more than other radicals, producing a series of relatively low-toxicity small molecular intermediates. A simplified kinetic model consisting of mass transfer of ATZ and HClO, •OH generation, and ATZ oxidation by •OH on the goethite surface was developed to simulate iron corrosion scale-triggered residual chlorine oxidation of organic compounds in a WDS. The model was validated by comparing the fitting results to the experimental data. Moreover, the model was comprehensively applicable to cases in which various inorganic ions (Ca2+, Na+, HCO3-, and SO42-) and natural organic matter were present. With further optimization, the model may be employed to predict the migration and accumulation of persistent organic pollutants under real environmental conditions in the WDSs.


Asunto(s)
Contaminantes Químicos del Agua , Cinética , Radicales Libres/química , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Hierro/química , Compuestos de Hierro/química , Minerales/química
2.
J Asthma ; : 1-8, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39316453

RESUMEN

BACKGROUND AND AIMS: To construct a set of scientific and effective quality evaluation indicators of continuing care for children with asthma, and to promote the development of continuing care for children with asthma toward a more specialized and standardized direction. METHODS: Through literature research and semi-structured interview, the item pool of evaluation index was drawn up, and the first draft of expert inquiry questionnaire was formed based on the three-dimensional quality theoretical model of structure-process-result, and the construction of quality evaluation index was completed through two rounds of expert inquiry and analytic hierarchy process. RESULTS: The effective recovery rate was 94.44% in the first round and 100.00% in the second round, the expert authority coefficient was 0.852 and 0.863, and the Kendal coordination coefficient was 0.129 and 0.126, respectively (p < 0.01). Finally, the evaluation index of continuing care quality for children with asthma was formed, including 3 first-level indicators, 9 s-level indicators and 36 third-level indicators, and then the weight and combination weight of each index were obtained by AHP. CONCLUSIONS: The evaluation index of continuing care quality for children with asthma is scientific and specific, which is of great significance to the improvement of continuing care quality for children with asthma.

3.
Environ Sci Technol ; 57(42): 16131-16140, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37812398

RESUMEN

Improving the wettability of carbon-based catalysts and overcoming the rate-limiting step of the Mn+1/Mn+ cycle are effective strategies for activating peroxymonosulfate (PMS). In this study, the coupling of Co-NC, layered double hydroxide (LDH), and CoSx heterostructure (CoSx@LDH@Co-NC) was constructed to completely degrade ofloxacin (OFX) within 10 min via PMS activation. The reaction rate of 1.07 min-1 is about 1-2 orders of magnitude higher than other catalysts. The interfacial effect of confined Co-NC and layered double hydroxide (LDH) not only enhanced the wettability of catalysts but also increased the vacancy concentration; it facilitated easier contact with the interface reactive oxygen species (ROS). Simultaneously, reduced sulfur species (CoSx) accelerated the Co3+/Co2+ cycle, acquiring long-term catalytic activity. The catalytic mechanism revealed that the synergistic effect of hydroxyl groups and reduced sulfur species promoted the formation of 1O2, with a longer lifespan and a longer migration distance, and resisted the influence of nontarget background substances. Moreover, considering the convenience of practical application, the CoSx@LDH@Co-NC-based catalytic membrane was prepared, which had zero discharge of OFX and no decay in continuous operation for 5.0 h. The activity of the catalytic membrane was also verified in actual wastewater. Consequently, this work not only provides a novel strategy for designing excellent catalysts but also is applicable to practical organic wastewater treatment.


Asunto(s)
Carbono , Ofloxacino , Peróxidos , Azufre , Hidróxidos , Antibacterianos
4.
Environ Sci Technol ; 56(20): 14409-14417, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36173643

RESUMEN

Electrochemical advanced oxidation processes (EAOPs) are promising technologies for perfluorooctanoic acid (PFOA) degradation, but the mechanisms and preferred pathways for PFOA mineralization remain unknown. Herein, we proposed a plausible primary pathway for electrochemical PFOA mineralization using density functional theory (DFT) simulations and experiments. We neglected the unique effects of the anode surface and treated anodes as electron sinks only to acquire a general pathway. This was the essential first step toward fully revealing the primary pathway applicable to all anodes. Systematically exploring the roles of valence band holes (h+), hydroxyl radicals (HO•), and H2O, we found that h+, whose contribution was previously underestimated, dominated PFOA mineralization. Notably, the primary pathway did not generate short-chain perfluoroalkyl carboxylic acids (PFCAs), which were previously thought to be the main degradation intermediates, but generated other polyfluorinated alkyl substances (PFASs) that were rapidly degraded upon formation. Also, we developed a simplified kinetic model, which considered all of the main processes (mass transfer with electromigration included, surface adsorption/desorption, and oxidation on the anode surface), to simulate PFOA degradation in EAOPs. Our model can predict PFOA concentration profiles under various current densities, initial PFOA concentrations, and flow velocities.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Caprilatos/química , Ácidos Carboxílicos , Electrodos , Fluorocarburos/análisis , Oxidación-Reducción , Contaminantes Químicos del Agua/química , Técnicas Electroquímicas
5.
BMC Cardiovasc Disord ; 22(1): 177, 2022 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-35430800

RESUMEN

BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2) has been taken as a biomarker of inflammation in patients with acute coronary diseases. Regular exercise rehabilitation could attenuate inflammation and promote the rehabilitation of coronary heart disease (CHD). The level of Lp-PLA2 is negatively correlated with 6-min walk test (6-MWT). The exercise prescription of appropriate intensity is the basis of exercise rehabilitation. 6-MWT is associated with maximal oxygen consumption, and can be used to determine the intensity of exercise prescription guiding patients how to do exercise rehabilitation. The aim of this study was to observe the benefit of 6-MWT guided exercise rehabilitation on the level of Lp-PLA2 in patients with CHD undergoing percutaneous coronary intervention (PCI). METHODS: We prospectively, consecutively enrolled 100 patients between Dec 2018 and Dec 2020 in the fourth ward of the Department of Cardiology, Yuebei People's Hospital Affiliated to Shantou University. Eligible patients were 1:1 divided into Group A, with no exercise rehabilitation, and Group B, with regular exercise rehabilitation, using random number table method of simple randomization allocation. Clinical data such as general information, the profile of lipids and the level of Lp-PLA2 were collected at baseline and at 12-week follow-up. RESULTS: There were no statistically significant differences of the percentages of gender, hypertension, type-2 diabetes mellitus (T2DM), the profile of lipids and level of Lp-PLA2 between the groups at baseline (P > 0.05). The level of Lp-PLA2 decreased at 12-week follow-up, moreover, the decline of the Lp-PLA2 level in Group B was more significant than that in Group A (t = 2.875, P = 0.005). Multivariate linear regression analysis indicated that exercise rehabilitation was independently correlated with the level of Lp-PLA2 (ß' = - 0.258, t = - 2.542, P = 0.013). CONCLUSION: Exercise rehabilitation for 12 weeks guided by 6-MWT can further reduce the level of LP-PLA2 in patients with CHD undergoing PCI. Trial registration This trial was registered on the Chinese Clinical Trial Registry: ChiCTR2100048124, registered 3 July 2021- Retrospectively registered. The study protocol adheres to the CONSORT guidelines.


Asunto(s)
Enfermedad Coronaria , Intervención Coronaria Percutánea , 1-Alquil-2-acetilglicerofosfocolina Esterasa , Biomarcadores , Enfermedad Coronaria/diagnóstico , Humanos , Inflamación , Lípidos , Intervención Coronaria Percutánea/efectos adversos , Estudios Prospectivos , Prueba de Paso
6.
Environ Sci Technol ; 53(23): 13784-13793, 2019 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-31687808

RESUMEN

Reducing energy use is crucial to commercialize electrochemical oxidation technologies. We developed a three-dimensional (3-D) electrochemical system that can significantly reduce the applied voltage and effectively degrade organic contaminants in low-ionic-strength wastewaters. The 3-D system consisted of a composite wire mesh anode (composed of blue TiO2 nanotubes covered with SnO2-Sb2O3), a proton exchange membrane, and a stainless-steel wire mesh cathode, which were compressed firmly together. For the 3-D system, we placed the anode of a 3-D electrode toward the wastewater that flowed past the anode. Both the two-dimensional (2-D) and 3-D systems had the same anode and cathode. We found that the 3-D system could reduce the applied voltage by 75.7% and reduce the electrical efficiency per log order reduction (EE/O) by 73% for 0.001 M Na2SO4. For Na2SO4 concentrations greater than 0.05 M, the 2-D system had a slightly lower EE/O. We also compared the EE/O of electrochemical advanced oxidation processes (EAOPs) with that of other advanced oxidation processes (UV/H2O2, UV/persulfate, O3/H2O2, UV/ TiO2, and UV/chlorine). We found that EAOPs have a much higher EE/O for low BA concentrations (20 mg/L) and a much lower EE/O for high BA concentrations (2000 mg/L).


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Técnicas Electroquímicas , Electrodos , Peróxido de Hidrógeno , Concentración Osmolar , Oxidación-Reducción
7.
Cancer Med ; 13(19): e70257, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39387501

RESUMEN

BACKGROUD: Cancer-related cognitive impairment is one of the common complications in children with cancer, but our understanding of their experience with cognitive deficits remains limited. From the perspective of parents, this study aimed to explore the distress and demands faced by children with cancer-related cognitive impairment, to provide references for developing targeted intervention strategies for cancer children. METHODS: We used a purposeful sampling method to conduct semi-structured interviews with the parents of 18 children with cancer-related cognitive impairment. The transcripts were analyzed using Colaizzi's method. RESULTS: Three categories and 11 subcategories were obtained from the data analysis, including diverse levels of cognitive impairment in children (speech communication difficulties, impaired executive function, attention deficit, and intellectual disability), persistent negative emotions (anxiety and worry, complaints and resentment, negative avoidance and positive experiences after psychological adjustment), multiple needs (need for disease information, need for professional management, and an urgent need for more external support). CONCLUSION: Parents of children with cancer-related cognitive impairment face a significant psychological burden, coupled with confusion and numerous inquiries regarding the symptoms and management of their children's cognitive impairment. It is imperative for medical professionals to strengthen the dissemination of information related to cancer-associated cognitive impairments, while promptly recognizing and intervening in related symptoms. Rational allocation of resources, establishment of targeted support systems, and enhancement of social acceptance may be the key points that policymakers could consider. These efforts hold immense significance, as they play a pivotal role in elevating cognitive capabilities and enhancing the overall quality of life for children with cancer.


Asunto(s)
Disfunción Cognitiva , Neoplasias , Padres , Investigación Cualitativa , Humanos , Neoplasias/psicología , Neoplasias/complicaciones , Femenino , Niño , Masculino , Padres/psicología , Disfunción Cognitiva/psicología , Disfunción Cognitiva/etiología , China , Adolescente , Adulto , Estrés Psicológico/psicología , Estrés Psicológico/etiología , Preescolar , Distrés Psicológico
8.
Helicobacter ; 18(2): 124-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23121308

RESUMEN

BACKGROUND: Helicobacter pylori (H. pylori) infection stimulates the production of proinflammatory cytokines associated with the development of atherosclerosis. Levels of circulating interleukin-18 (IL-18) have been positively correlated with carotid intima-media thickness (IMT) and coronary plaque area and have identified IL-18 levels as important predictors of coronary events and cardiovascular mortality. This study aimed to examine the relationship between serum IL-18 and H. pylori-IgG antibody as a sign of H. pylori infection in patients with carotid atherosclerosis. METHODS: The carotid IMT, traditional atherosclerotic risk factors, levels of serum H. pylori-IgG and IL-18 were measured in 573 health checkup examinees. RESULTS: Serum IL-18 and H. pylori-IgG levels were significantly increased in subjects with increased IMT in comparison with those with normal IMT. In subjects with increased IMT, serum H. pylori-IgG was positively correlated with serum IL-18 (r = .402, p = .002), and the association was independent of traditional atherosclerotic risk factors (ß = 0.310, p < .001). CONCLUSIONS: In health checkup examinees with increased IMT, serum IL-18 and H. pylori-IgG were independently correlated and were significantly higher than in subjects with normal IMT.


Asunto(s)
Enfermedades de las Arterias Carótidas/etiología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Interleucina-18/sangre , Adulto , Anciano , Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/inmunología , Grosor Intima-Media Carotídeo , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad
9.
Micromachines (Basel) ; 13(10)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36295942

RESUMEN

Wide-range flexible pressure sensors are in difficulty in research while in demand in application. In this paper, a wide-range capacitive flexible pressure sensor is developed with the foaming agent ammonium bicarbonate (NH4HCO3). By controlling the concentration of NH4HCO3 doped in the polydimethylsiloxane (PDMS) and repeating the curing process, pressure-sensitive dielectrics with various porosity are fabricated to expand the detection range of the capacitive pressure sensor. The shape and the size of each dielectric is defined by the 3D printed mold. To improve the dielectric property of the dielectric, a 1% weight ratio of multi-walled carbon nanotubes (MWCNTs) are doped into PDMS liquid. Besides that, a 5% weight ratio of MWCNTs is dispersed into deionized water and then coated on the electrodes to improve the contact state between copper electrodes and the dielectric. The laminated dielectric layer and two electrodes are assembled and tested. In order to verify the effectiveness of this design, some reference devices are prepared, such as sensors based on the dielectric with uniform porosity and a sensor with common copper electrodes. According to the testing results of these sensors, it can be seen that the sensor based on the dielectric with various porosity has higher sensitivity and a wider pressure detection range, which can detect the pressure range from 0 kPa to 1200 kPa and is extended to 300 kPa compared with the dielectric with uniform porosity. Finally, the sensor is applied to the fingerprint, finger joint, and knee bending test. The results show that the sensor has the potential to be applied to human motion detection.

10.
Environ Int ; 140: 105813, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32480113

RESUMEN

This paper reports on the development of macroporous flow-through anodes. The anodes comprised an enhanced TiO2 nanotube array (ENTA) that was grown on three macroporous titanium substrates (MP-Ti) with nominal pore sizes of 10, 20, and 50 µm. The ENTA was then covered with SnO2-Sb2O3. We refer to this anode as the MP-Ti-ENTA/SnO2-Sb2O3 anode. The morphology, pore structure, and electrochemical properties of the anode were characterized. Compared with the traditional NTA layer, we found that the MP-Ti-ENTA/SnO2-Sb2O3 anode has a service lifetime that was 1.56 times larger than that of MP-Ti-NTA/SnO2-Sb2O3. We used 2-methyl-4-isothiazolin-3-one (MIT), a common biocide, as the target pollutant. We evaluated the impact of the operating parameters on energy efficiency and the oxidation rate of MIT. Furthermore, the apparent rate constants were 0.38, 1.63, and 1.24 min-1 for the 10, 20, and 50 µm nominal pore sizes of the MP-Ti substrates, respectively, demonstrating the different coating-loading mechanisms for the porous substrate. We found that hydroxyl radicals were the dominant species in the MIT oxidation in the HO radical scavenging experiments. The radical and nonradical oxidation contributions to the MIT degradation for different current densities were quantitatively determined as 72.1%-74.8% and 25.2%-27.9%, respectively. Finally, we summarized the oxidation performance for MIT destruction for (1) the published literature on various advanced oxidation technologies, (2) the published literature on various anodes, and (3) our flow-by and -through anodes. Accordingly, we found that our flow-through anode has a much lower electrical efficiency per order value (0.58 kWh m-3) than the flow-by anodes (6.85 kWh m-3).


Asunto(s)
Nanotubos , Contaminantes Químicos del Agua , Electrodos , Oxidación-Reducción , Titanio
11.
Sci Total Environ ; 619-620: 600-605, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29156278

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) pollution in urban river sediments is a serious problem to ecological systems and human health. We examined novel remediation approaches, using a biochar amendment combined with bioaugmentation or/and nitrate stimulation, to degrade phenanthrene in sediment. Biochar amendment combined with nitrate stimulation enhanced phenanthrene degradation by 2.3 times that of the control and 1.9 times that of biochar alone. Nitrate stimulation altered the microbial succession and encouraged the growth of potential nitrate-reducing PAH-degraders Thiobacillus and Stenotrophomonas. Biochar was an excellent sorbent for phenanthrene and the shelter that it provided PAH-degraders increased contact between phenanthrene and PAH-degraders. Biochar also enhanced the aging effects of phenanthrene and reduced the ecological risk by 7.7% to 11%. These results suggest that biochar amendment combined with nitrate stimulation can achieve high-efficiency phenanthrene degradation in sediments.

13.
Sci Rep ; 6: 23134, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26976450

RESUMEN

Traditional risk assessment and source apportionment of sediments based on bulk polycyclic aromatic hydrocarbons (PAHs) can introduce biases due to unknown aging effects in various sediments. We used a mild solvent (hydroxypropyl-ß-cyclodextrin) to extract the bioavailable fraction of PAHs (a-PAHs) from sediment samples collected in Pearl River, southern China. We investigated the potential application of this technique for ecological risk assessments and source apportionment. We found that the distribution of PAHs was associated with human activities and that the a-PAHs accounted for a wide range (4.7%-21.2%) of total-PAHs (t-PAHs), and high risk sites were associated with lower t-PAHs but higher a-PAHs. The correlation between a-PAHs and the sediment toxicity assessed using tubificid worms (r = -0.654, P = 0.021) was greater than that from t-PAH-based risk assessment (r = -0.230, P = 0.472). Moreover, the insignificant correlation between a-PAH content and mPEC-Q of low molecular weight PAHs implied the potential bias of t-PAH-based risk assessment. The source apportionment from mild extracted fractions was consistent across different indicators and was in accordance with typical pollution sources. Our results suggested that mild extraction-based approaches reduce the potential error from aging effects because the mild extracted PAHs provide a more direct indicator of bioavailability and fresher fractions in sediments.


Asunto(s)
Sedimentos Geológicos/química , Hidrocarburos Policíclicos Aromáticos/química , Contaminantes Químicos del Agua/química , Animales , China , Ciudades , Monitoreo del Ambiente/métodos , Oligoquetos/efectos de los fármacos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo/métodos , Ríos , Contaminantes Químicos del Agua/toxicidad
14.
Chin Med J (Engl) ; 126(5): 937-41, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23489805

RESUMEN

BACKGROUND: The pathophysiology of type 2 diabetes is progressive pancreatic beta cell failure with consequential reduced insulin secretion. Glucotoxicity results in the reduction of beta cell mass in type 2 diabetes by inducing apoptosis. Autophagy is essential for the maintenance of normal islet architecture and plays a crucial role in maintaining the intracellular insulin content by accelerating the insulin degradation rate in beta cells. Recently more attention has been paid to the effect of autophagy in type 2 diabetes. The regulatory pathway of autophagy in controlling pancreatic beta cells is still not clear. The aim of our study was to evaluate whether liraglutide can inhibit apoptosis and modulate autophagy in vitro in insulinoma cells (INS-1 cells). METHODS: INS-1 cells were incubated for 24 hours in the presence or absence of high levels of glucose, liraglutide (a long-acting human glucagon-like peptide-1 analogue), or 3-methyadenine (3-MA). Cell viability was measured using the Cell Counting Kit-8 (CCK8) viability assay. Autophagy of INS-1 cells was tested by monodansylcadaverine (MDC) staining, an autophagy fluorescent compound used for the labeling of autophagic vacuoles, and by Western blotting of microtubule-associated protein I light chain 3 (LC3), a biochemical markers of autophagic initiation. RESULTS: The viability of INS-1 cells was reduced after treatment with high levels of glucose. The viability of INS-1 cells was reduced and apoptosis was increased when autophagy was inhibited. The viability of INS-1 cells was significantly increased by adding liraglutide to supplement high glucose level medium compared with the cells treated with high glucose levels alone. CONCLUSIONS: Apoptosis and autophagy were increased in rat INS-1 cells when treated with high level of glucose, and the viability of INS-1 cells was significantly reduced by inhibiting autophagy. Liraglutide protected INS-1 cells from high glucose level-induced apoptosis that is accompanied by a significant increase of autophagy, suggesting that liraglutide plays a role in beta cell apoptosis by targeting autophagy. Thus, autophagy may be a new target for the prevention or treatment of diabetes.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Péptido 1 Similar al Glucagón/análogos & derivados , Glucosa/farmacología , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Péptido 1 Similar al Glucagón/farmacología , Insulinoma/patología , Liraglutida , Ratas
15.
Autophagy ; 7(1): 12-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20935505

RESUMEN

Autophagy is an intracellular catabolic system, which enables cells to capture cytoplasmic components for degradation within lysosomes. Autophagy is involved in development, differentiation and tissue remodeling in various organisms, and is also implicated in certain diseases. Recent studies demonstrate that autophagy is necessary to maintain architecture and function of pancreatic beta cells. Altered autophagy is also involved in pancreatic beta cell death. Whether autophagy plays a protective or harmful role in diabetes is still not clear. In this review, we will summarize the current knowledge about the role of autophagy in pancreatic beta cell and diabetes.


Asunto(s)
Autofagia , Diabetes Mellitus/patología , Células Secretoras de Insulina/patología , Humanos , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Modelos Biológicos
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