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1.
Ecotoxicol Environ Saf ; 170: 259-266, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30529921

RESUMEN

In this study, we investigated the degradation kinetics of chlorpyrifos, an organophosphorus (OP) compound, using ferrate(VI), and investigated the potential of this iron-based chemical oxidant on chlorpyrifos removal from water and wastewater treatments. A series of kinetic experiments were conducted to evaluate the influence of various environmental factors, such as pH, oxidant dosages, as well as the presence of anions, cations, humic acid (HA), and different water matrices. Chlorpyrifos was completely removed within 300 s under the following optimum conditions: [chlorpyrifos]0 = 1 µM, [Fe(VI)]0:[chlorpyrifos]0 = 100:1, T = 25 °C, and pH = 7.0. Anions such as Cl-, SO42-, NO3-, and HCO3- and cations such as Fe3+, Cu2+, and NH4+ did not appear to influence the removal of chlorpyrifos. However, the presence of Ca2+, Mg2+, and HA in water inhibited the degradation of chlorpyrifos. Experiments on removing chlorpyrifos from tap water, river water, and synthetic wastewater were performed to demonstrate the practical applications of Fe(VI). Ten oxidation products of chlorpyrifos were identified using liquid chromatography-quadrupole-time-of flight-mass spectrometry (LC-Q-TOF-MS), and their structures were further elucidated using MS/MS spectra. Then, two degradation pathways were preliminarily proposed including the oxidation of the P = S bond, cleavage of C-O bond, and hydroxyl substitution reaction. In general, Fe(VI) could be used as an efficient technology for chlorpyrifos removal from water and wastewater treatments.


Asunto(s)
Cloropirifos/análisis , Hierro/química , Oxidantes/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Agua Dulce/química , Sustancias Húmicas/análisis , Concentración de Iones de Hidrógeno , Cinética , Modelos Teóricos , Oxidación-Reducción , Aguas Residuales/química
2.
J Hazard Mater ; 465: 133398, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38160556

RESUMEN

In this work, nitrogen-doped SiO2 (N-SiO2) was successfully synthesized to develop an "adsorption-photocatalytic degradation" water purification technology to remove hydrophobic organic contaminants (HOCs). As a representative of HOCs, decabromodiphenylethane (DBDPE) could be efficiently degraded under simulated sunlight after adsorption on the surface of N-SiO2. Due to the generation of reactive oxygen species (ROS) and silicon-based radicals, the photodegradation rate of DBDPE on water-SiO2 interface was 1.5-fold higher than that in water. Furthermore, the transformation pathways of DBDPE on N-SiO2 surface were compared with that in water. Bond breaking and debromination reactions were the common pathways, while hydroxylation and silicon-based substitution reactions were the specific transformation pathways for DBDPE on the surface of N-SiO2. Density functional theory (DFT) calculation was used to reveal the generation mechanism of silicon-based radicals and determine the rationality of the involvement of silicon-based radicals in DBDPE transformation. The energy barriers of silicon-based substitution reaction were comparable to that of hydroxylation and debromination reactions, which confirmed the plausibility of the generation of silicon-based substitution products. This study provides an efficient method for the disposal of HOCs, which also gives some new insights into the conversion mechanism of organic pollutants mediated by silicon-based radicals.

3.
Chemosphere ; 349: 140952, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38101481

RESUMEN

The degradation process of bisphenol S (BPS) in ozone/peroxymonosulfate (O3/PMS) system was systematically explored. The results showed that the removal efficiency of BPS by O3 could be significantly improved with addition of PMS. Compared with ozonation alone, the pseudo-first-order constant (kobs) was increased by 2-5 times after adding 400 µM PMS. In O3/PMS system, accelerated removal of BPS was observed under neutral and alkaline conditions. The removal efficiency of BPS reached 100% after 40 s of reaction at pH 7.0, with the kobs of 0.098 s-1. Moreover, Cu2+ had a catalytic effect on the O3/PMS system, because it could catalyze the decomposition of ozone and PMS to produce •OH and SO4•-, respectively. Electron paramagnetic resonance illustrated that •OH and SO4•- were the reactive species in O3/PMS system. Twelve intermediates were identified by mass spectrometry, and the degradation reactions in O3/PMS system mainly included hydroxylation, sulfate addition, polymerization and ß-scission. Finally, the toxicity of the products was evaluated by the EOCSAR program. Our results introduce an efficient method for BPS removal and would provide some guidance for the development of O3-based advanced oxidation technology.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Ozono/química , Contaminantes Químicos del Agua/análisis , Peróxidos/química , Oxidación-Reducción
4.
Neurobiol Aging ; 136: 111-124, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342072

RESUMEN

In mammals, thick axonal calibers wrapped with heavy myelin sheaths are prevalent in the auditory nervous system. These features are crucial for fast traveling of nerve impulses with minimal attenuation required for sound signal transmission. In particular, the long-range projections from the cochlear nucleus - the axons of globular bush cells (GBCs) - to the medial nucleus of the trapezoid body (MNTB) are tonotopically organized. However, it remains controversial in gerbils and mice whether structural and functional adaptations are present among the GBC axons targeting different MNTB frequency regions. By means of high-throughput volume electron microscopy, we compared the GBC axons in full-tonotopy-ranged MNTB slices from the C57BL/6 mice at different ages. Our quantification reveals distinct caliber diameter and myelin profile of the GBC axons with endings at lateral and medial MNTB, arguing for modulation of functionally heterogeneous axon subgroups. In addition, we reported axon-specific differences in axon caliber, node of Ranvier, and myelin sheath among juvenile, adult, and old mice, indicating the age-related changes of GBC axon morphology over time. These findings provide structural insight into the maturation and degeneration of GBC axons with frequency tuning across the lifespan of mice.


Asunto(s)
Vías Auditivas , Núcleo Coclear , Ratones , Animales , Vías Auditivas/fisiología , Microscopía Electrónica de Volumen , Ratones Endogámicos C57BL , Axones/fisiología , Núcleo Coclear/fisiología , Vaina de Mielina , Mamíferos
5.
Environ Pollut ; 346: 123621, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38402942

RESUMEN

Considering that waste incineration fly ash is the main carrier of dioxins and can migrate over long distances in the atmosphere, it is of great significance to study the photochemical transformation behavior of dioxins on the surface of fly ash. In this work, 2-chlorodibenzo-p-dioxin (2-CDD) was selected to conduct a systematic photochemical study. The influence of various factors on the photodegradation of 2-CDD were first explored, and the results showed that small particle size of fly ash, low concentration of 2-CDD and appropriate level of humidity were more conducive to photodegradation, with the highest degradation percentage reaching 76%-84%. The components of fly ash (Zn (Ⅱ), Al (Ⅲ), Cu (Ⅱ) and SiO2) also had a certain promoting effect on the degradation of 2-CDD, which increases the degradation efficiency by 10%-20%, because they could act as effective photocatalysts to produce free radicals for reaction. With a higher total light exposure intensity, natural light environments led to a more complete degradation of 2-CDD than laboratory Xe lamp irradiation (90% degradation Vs. 79% degradation). Based on chemical probe and radical quenching experiment, hydroxyl radical also contributed to 2-CDD photodegradation on fly ash. A total of 16 intermediate products were detected by mass spectrometry analysis, and four initial reaction pathways of 2-CDD were speculated in the process, including dechlorination, ether bond cleavage, hydroxyl substitution, and hydroxyl addition. According to the results of density functional theory calculation, the reaction channels of ether bond cleavage and •OH attack were determined. The toxicity assessment software tool (TEST) was used to assess the toxicity and bioconcentration coefficient of reaction products, and it was found that the overall toxicity of the photodegradation products was reduced. This study would provide new insights into the environmental fate of dioxins during long-range atmospheric migration process.


Asunto(s)
Dioxinas , Metales Pesados , Eliminación de Residuos , Residuos Sólidos/análisis , Dioxinas/análisis , Ceniza del Carbón/análisis , Fotólisis , Dióxido de Silicio , Incineración/métodos , Éteres , Eliminación de Residuos/métodos , Carbono/química , Metales Pesados/análisis
6.
Sci Total Environ ; 924: 171586, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461975

RESUMEN

Developing efficient and low-cost photocatalytic materials is essential for removing polychlorinated biphenyls (PCBs). In this work, the photodegradation process of fourteen representative polychlorinated biphenyls (PCBs) in both water/nitrogen-doped SiO2 (N-SiO2) and air/N-SiO2 systems was studied. The photodegradation kinetics of PCBs is consistent with the pseudo-first-order kinetic equation. The variation in the degradation effects of different PCBs in the two systems is primarily related to the position of the Cl substituent and the effective absorption wavelength range of PCBs. A total of fourteen intermediates for 4'-Dichlorobiphenyl (PCB-15), 2,2',4,4',6,6'-Hexachlorobiphenyl (PCB-155), and 2,2',3,3',4,4',5,5',6,6'-Decachlorobiphenyl (PCB-209) generated from four reaction pathways were identified based on both mass spectrometry analysis and theoretical calculations. Using the values of lnk (k denotes pseudo-first-order kinetic constants) for the 11 PCBs in the training set and the calculated molecular and structural parameters, quantitative structure-activity relationship (QSAR) models for the two systems were constructed by using multiple linear regression (MLR) method to better understand the factors affecting the photodegradation rate of PCBs. The QSAR equations were obtained with Cl atom substitution at position 3 (N3) as the main parameter, which were lnk = -1.98 - 0.19 N3 for the water/N-SiO2 system and lnk = -1.56 - 0.34 N3 for the air/N-SiO2 system, with the correlation coefficient (R2) of 0.66 and 0.73, leave-one-out cross-validation (Q2LOO) of 0.51 and 0.59, respectively, and bootstrapping validation coefficients (Q2BOOT) values of both 0.74, confirming that the models were well fitted and showed high robustness and prediction ability. This study provides valuable insights into photocatalytic degradation studies of PCBs.

7.
Int J Surg ; 110(5): 2583-2592, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38349219

RESUMEN

BACKGROUND: Few studies have reported the coronal constitutional alignment of the lower limbs in mainland China. This study aimed to analyse the distribution of the coronal plane alignment of the knee (CPAK) classification in the osteoarthritic (OA) and healthy Chinese populations. MATERIALS AND METHODS: The CPAK distributions of 246 patients (477 knees) with OA and 107 healthy individuals (214 knees) were retrospectively examined using long-leg radiographs. Radiological measurements and CPAK classification of different Kellgren-Lawrence grades in patients with unilateral total knee arthroplasty (TKA) were compared. The clinical outcomes of patients with CPAK type I who underwent mechanical alignment or restricted kinematic alignment during TKA were examined. RESULTS: The most common distributions in the OA and healthy groups were type I and type II, respectively. In patients who underwent unilateral TKA, the most common distribution of knees graded as Kellgren-Lawrence 3-4 was type I. However, the most common distributions of contralateral knees graded as Grade 0-2 were type I and II. For patients with CPAK type I, the mechanical alignment and restricted kinematic alignment groups did not differ significantly concerning postoperative clinical outcomes at 3 months. CONCLUSION: The most common distributions in Chinese osteoarthritic and healthy populations were types I and II, respectively. In addition, OA progression may lead to changes in the CPAK classification.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Articulación de la Rodilla , Osteoartritis de la Rodilla , Humanos , Estudios Retrospectivos , Masculino , Femenino , Osteoartritis de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Persona de Mediana Edad , Estudios Transversales , China , Anciano , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Radiografía , Adulto , Pueblos del Este de Asia
8.
J Hazard Mater ; 452: 131252, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36963191

RESUMEN

To reveal the fate of anthracene (ANT) in soil, the photodegradation behavior of ANT was systematically studied using SiO2 to simulate a soil environment. Under xenon lamp irradiation, more than 90% of ANT loaded on SiO2 could be removed after 240 min. Moreover, the effects of water content, chloride ions (Cl-) and humic acid (HA) were examined. It was found that the presence of water and HA can significantly inhibit the photolysis of ANT on SiO2, while the addition of chloride alone has no obvious effect. However, when water is present, the inhibition effect of chloride became more obvious. According to radical quenching experiments and electron paramagnetic resonance (EPR) spectra, hydroxyl radicals (•OH) and chlorine radicals (Cl•) were formed in the system. Possible reaction pathways were speculated based on products identified by mass spectrometry. ANT was attacked by •OH to form hydroxylated products, which can be further hydroxylated and oxidized with the final formation of ring-opening products. ANT directly excited by light may also react with Cl• to produce chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs). Finally, the experimental results were verified on real soil. This study provides important information for understanding the photochemical transformation mechanism of ANT at the soil/air interface.

9.
Chemosphere ; 316: 137774, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36642137

RESUMEN

The removal of Bisphonel AF (BPAF) by zero-valent iron activated persulfate (Fe0/PS) system was systematically evaluated in this work. 30.0 µM BPAF was removed by 94.4% in 60 min of treatment under optimal conditions of pH = 3.0 and [PS] = [Fe0] = 3.0 mM. Cl- significantly accelerated the removal of BPAF, resulting from accelerated Fe2+ release and reactive chlorine species (RCS) formation. Liquid chromatography-time-of-flight-mass spectrometry identified thirteen degradation products, and bond breaking, coupling reactions, hydroxylation and sulfate addition were considered as the major transformation pathways. When Cl- was present, six new chlorinated byproducts were also generated. Based on density functional theory (DFT) calculations, the occurrence of radical addition reactions was verified and the preferential reaction channels were determined. Significantly BPAF degradation products were less toxic, according to toxicity assessment by the ECOSAR program. Moreover, a high removal efficiency of BPAF (>90%) was also obtained in the three actual water matrixes. The present work demonstrates the feasibility of Fe0/PS system for treating BPAF, which could also provide new insights into the influence of coexisting Cl- on the environmental fate of organic pollutants in sulfate radicals based advanced oxidation processes.


Asunto(s)
Cloruros , Contaminantes Químicos del Agua , Hierro/química , Cinética , Contaminantes Químicos del Agua/toxicidad , Oxidación-Reducción , Sulfatos/química
10.
Front Aging Neurosci ; 15: 1257618, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38076540

RESUMEN

Introduction: Impulse control disorder (ICD) is a common non-motor symptom of Parkinson's disease (PD), but its risk factors are still controversial. This study aimed to determine the prevalence of ICD in northern China and analyze the risk factors associated with ICD, multiple ICDs, and four subtypes. Methods: A total of 285 PD patients were enrolled in this study. Each patient was screened using the Questionnaire for Impulse and Compulsive Control Disorders (QUIP). Stepwise regression analysis was performed to identify independent risk factors, and a prediction model was developed. Results: The prevalence of ICD in the study population was 11.6%. Stepwise regression analysis showed that ICD was associated with disease duration, motor symptoms, dyskinesia, depression, REM sleep behavior disorder (RBD) and cognitive decline; multiple ICDs were related to coffee history, motor symptoms, dyskinesia, depression, apathy and RBD. The prediction model demonstrated good performance with AUC values of 0.93, 0.88, and 0.66 on the balanced train set, balanced test set, and the original imbalanced data set, respectively. Conclusion: The risk factors for PD-ICD are complex and influenced by regional economic and cultural backgrounds. Clarifying these factors and developing predictive models can help to delay or even prevent the development of ICD through early screening and intervention.

11.
Chemosphere ; 336: 139189, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37307926

RESUMEN

In this study, the oxidation of 1-naphthol (1-NAP) and 2-naphthol (2-NAP) by Fe(VI) was investigated. The impacts of operating factors were investigated through a series of kinetic experiments, including Fe(VI) dosages, pH and coexisting ions (Ca2+, Mg2+, Cu2+, Fe3+, Cl-, SO42-, NO3- and CO32-). Almost 100% elimination of both 1-NAP and 2-NAP could be achieved within 300 s at pH 9.0 and 25 °C. Cu2+ could significantly improve the degradation efficiency of 1-NAP and 2-NAP, but the impacts of other ions were negligible. The liquid chromatography-mass spectrometry was used to identify the transformation products of 1-NAP and 2-NAP in Fe(VI) system, and the degradation pathways were proposed accordingly. Electron transfer mediated polymerization reaction was the dominant transformation pathway in the elimination of NAP by Fe(VI) oxidation. After 300 s of oxidation, heptamers and hexamers were found as the final coupling products during the removal of 1-NAP and 2-NAP, respectively. Theoretical calculations demonstrated that the hydrogen abstraction and electron transfer reaction would easily occur at the hydroxyl groups of 1-NAP and 2-NAP, producing NAP phenoxy radicals for subsequent coupling reaction. Moreover, since the electron transfer reactions between Fe(VI) and NAP molecules were barrierless and could occur spontaneously, the theoretical calculation results also confirmed the priority of coupling reaction in Fe(VI) system. This work indicated that the Fe(VI) oxidation was an effective way for removing naphthol, which may help us understand the reaction mechanism between phenolic compounds with Fe(VI).


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Naftoles , Cinética , Oxidación-Reducción , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
12.
J Invest Dermatol ; 143(1): 67-77.e15, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35933036

RESUMEN

Although chronic spontaneous urticaria (CSU) is a common disease, GWASs of CSU are lacking. We aimed to identify susceptibility SNPs by performing a GWAS in Chinese Han adults with CSU. The discovery cohort included 430 CSU cases and 482 healthy controls. The GWAS findings were validated in 800 CSU cases and 900 healthy controls. Genetic, functional enrichment, and bioinformatic analyses of genome-wide significant SNPs were performed to assess the association between CSU and autoimmunity or atopy. Five genome-wide significant SNPs were identified: rs434124/LILRA3, rs61986182/IGHG1/2, rs73075571/TDGF1, rs9378141/HLA-G, and rs3789612/PTPN22. The first four SNPs were in linkage disequilibrium with autoimmune-related diseases‒associated SNPs and were cis-expression quantitative trait loci in immune cells. The five SNPs-annotated genes were significantly enriched in immune processes. Higher polygenic risk scores and allele frequencies of rs3789612∗T, rs9378141∗C, and rs73075571∗G were significantly associated with autoimmune-related CSU phenotypes, including positive antithyroglobulin IgG, positive anti-FcεRIα IgG, total IgE <40 IU/ml, and positive antithyroid peroxidase IgG but not with atopic or allergic sensitized CSU phenotypes. This GWAS of CSU identifies five risk loci and reveals that CSU shares genetic overlap with autoimmune diseases and that genetic factors predisposing to CSU mainly manifest through associations with autoimmune traits.


Asunto(s)
Enfermedades Autoinmunes , Urticaria Crónica , Urticaria , Humanos , Estudio de Asociación del Genoma Completo , Urticaria/genética , Enfermedad Crónica , Urticaria Crónica/genética , Enfermedades Autoinmunes/genética , Inmunoglobulina G , Proteína Tirosina Fosfatasa no Receptora Tipo 22 , Receptores Inmunológicos
14.
Chemosphere ; 299: 134397, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35337821

RESUMEN

The widespread use of polybrominated diphenyl ethers (PBDEs) inevitably leads to their occurrence in the atmosphere, soil, and sediment. Biomass, especially dry branches and fallen leaves, may act a large reservoir for PBDEs through atmospheric deposition or soil bioaccumulation. Thus, clarifying the sunlight-induced transformation behaviors of PBDEs on biomass is highly significant for our understanding on its natural self-purification process. In this work, the degradation kinetics and mechanisms of two common PBDEs congeners, decabromodiphenyl ether (BDE-209) and 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), on biomass were systematically studied under natural and simulated sunlight irradiation conditions. The highest photodegradation rate constant of BDE-209 and BDE-47 was observed on sour cherry (SC) and zoysia matrella (ZM), respectively, which was related to their larger light receiving area and poor crystallinity. Due to the higher apparent quantum efficiency, BDE-209 degrades faster than BDE-47 (0.063-0.223 vs 0.006-0.026 h-1). The sunlight self-purification cycle of BDE-209 and BDE-47 on biomass were 6 and 14 days, respectively, with the corresponding sunlight contribution in the range of 0.12-0.51 ng mW-1. Products analysis by GC-MS and HPLC-MS/MS revealed that the main reactions involved in the photodegradation of BDE-209 and BDE-47 on biomass were debromination, hydroxylation, cyclization, and C-O bond breaking reaction. Especially, it was firstly proposed that hydroxyl H in lignin from biomass participated in the formation of primary products, which were rationalized by density functional theory (DFT) calculations and control experiments.


Asunto(s)
Éteres Difenilos Halogenados , Bifenilos Polibrominados , Biomasa , Éteres Difenilos Halogenados/análisis , Fotólisis , Bifenilos Polibrominados/química , Suelo , Espectrometría de Masas en Tándem
15.
Water Res ; 226: 119316, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36369691

RESUMEN

As a class of emerging aquatic pollutants, alkylimidazole-based ionic liquids (AM-ILs) have received extensive attention due to the large acute toxicity to aquatic organisms. Therefore, in order to protect both aquatic organisms and human beings, it is necessary to seek an efficient and environmental-friendly technology for removal of AM-ILs from water bodies. In this work, we found that under simulated sunlight (Xe lamp) irradiation, periodate (KIO4, PI) could efficiently degrade 1-hexyl-2,3-dimethylimidazolium bromide ([HMMIm]Br), a representative AM-ILs with six carbon atoms in the side chain. Kinetics experiments on the degradation of [HMMIm]Br were performed, and the results showed that a high degradation efficiency (≥90.00%) of the cation ([HMMIm]+) was still maintained under harsh water conditions of strong acidity/alkaliny or with various non-target inorganic ions. More importantly, the anion of bromide ion (Br-) was not oxidized to the carcinogenic bromate (BrO3-) in current reaction system. The excited stated PI (marked as PI*) was detected by Laser flash photolysis, and it was an important reactive species for [HMMIm]+ degradation. As rationalized by theoretical calculations and scavenging experiments, the main oxidation mechanisms of [HMMIm]+ were hydroxyl radicals induced substitution reaction, PI* initiated electron and double oxygen transfer, and direct photolysis mediated chemical bond cleavage reaction, which contributed to 73%, 21%, and 6% of [HMMIm]+ degradation, respectively. Moreover, toxicity evaluation by ECOSAR software indicated that the oxidation products were generally less toxic to three aquatic organisms (fish, water flea, and green algae) than the target molecule [HMMIm]Br. In conclusion, this work proposed novel oxidation mechanisms of sunlight-activated PI system, and the findings may inspire further researches on the application of photoactivated hypervalent acids in water purification.


Asunto(s)
Líquidos Iónicos , Contaminantes Químicos del Agua , Animales , Humanos , Líquidos Iónicos/química , Luz Solar , Bromuros , Contaminantes Químicos del Agua/química , Fotólisis , Cinética , Imidazoles/química
16.
Chemosphere ; 295: 133907, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35151701

RESUMEN

As one of the first batch of persistent organic pollutants (POPs) included in Stockholm Convention, hexachlorobenzene (HCB) has attracted great attention because of its wide occurrence and great environmental risks. Considering the easy adsorption of HCB on solids and the complexity of natural particles, we systematically investigated the photodegradation of HCB on the surface of silica gel (SG) in aqueous solution in this work to reveal its fate in natural waters. Under mercury lamp irradiation, more than 90% of HCB loaded on SG could be removed after 240 min. Moreover, the effects of solution pH and water constituents were examined, and results showed that the presence of NO2-, NO3-, Fe3+ and humic acid (HA) significantly inhibited the reaction due to the scavenging of ROS and/or competitive absorption of light. According to radical quenching experiments and electron paramagnetic resonance (EPR) spectra, hydroxyl radicals and singlet oxygen generated on the surface of SG could participate in the transformation of HCB, but •OH played a dominant role. Based on products identified by high performance liquid chromatography-mass spectrometry (HPLC-MS) and gas chromatography-mass spectrometry (GC-MS), two main pathways were proposed for the removal of HCB, including dechlorination and hydroxylation which represent direct and indirect photodegradation, respectively, and the occurrence of these two reactions was further supported by density functional theory (DFT) calculations. From the quantitative analysis of penta-chlorobenzene, it was estimated that dechlorination and hydroxylation contributed to approximately 44.4% and 55.6% of initial HCB degradation, respectively. Furthermore, toxicity predictions by the ecological structure-activity relationship model (ECOSAR) suggested that the toxicity of HCB was decreased in the photodegradation process. This study would provide important information for understanding the photochemical transformation mechanism of HCB at the solid/water interface.


Asunto(s)
Hexaclorobenceno , Agua , Hexaclorobenceno/química , Sustancias Húmicas/análisis , Cinética , Fotólisis , Agua/química
17.
Brain Sci ; 12(10)2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36291277

RESUMEN

BACKGROUND: Apathy is a common non-motor symptom of Parkinson's disease (PD). The influencing factors of apathy are currently controversial. This study aimed to describe the clinical characteristics of PD-associated apathy and to analyze the associated risk factors. METHODS: Two hundred patients diagnosed with PD were selected. Included patients were divided into an apathetic group and a non-apathetic group. Demographic and clinical data, motor symptoms, non-motor symptoms and medication use of the two groups were assessed. RESULTS: The incidence of apathy was 69%. Demographic and clinical data, motor symptoms, non-motor symptoms and medications use were statistically significant. CONCLUSIONS: PD patients with more severe motor symptoms, cognitive impairment, depression, anxiety, RBD, excessive daytime sleep, fatigue, low education level, long disease course, poor quality of life and lower DA dosage are more prone to apathy. Cognitive function, quality of life, educational level, DA and LEDD are independent risk factors for apathy.

18.
Water Res ; 222: 118953, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35964513

RESUMEN

This work systematically examined the capability of ferrate (Fe(VI)) for ammonia oxidation, revealing for the first time that bromide ions (Br-) played an important role in promoting the removal of ammonia in Fe(VI) system. In the presence of 10.0 mM Br-, the removal efficiency of ammonia was nearly 3.4 times that of the control, and 1.0 mM ammonia was almost completely removed after two rounds addition of 1.0 mM Fe(VI) in 60 min. PMSO probe test, electron paramagnetic resonance spectra and radical quenching experiments were employed to interpret the underlying promotion mechanism of Br-, and it was proposed that the formation of active bromine (HOBr/OBr-) played a dominant role in the enhanced oxidative removal of ammonia by Fe(VI). Further kinetic model simulations revealed that HOBr/OBr- and Fe(VI) were the two major reactive species in Fe(VI)/Br- system, accounting for 66.7% and 33.0% of ammonia removal, respectively. As the target contaminant, ammonia could quickly consume the generated HOBr/OBr-, thereby suppressing the formation of brominated disinfection byproducts. Finally, NO3- was identified as the dominant transformation product of ammonia, and density functional theory (DFT) calculations revealed that six reaction stages were involved in ammonia oxidation with the first step as the rate-limiting step. This work would enable the full use of coexisting bromides for effective removal of ammonia from natural waters or wastewaters by in situ Fe(VI) oxidation method.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Amoníaco , Bromuros , Bromo , Cinética , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
19.
Allergy Asthma Immunol Res ; 14(1): 131-142, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34983113

RESUMEN

Immunoglobulin (Ig) E and IgG anti-thyroid autoantibodies (AAbs) play important roles in the immunopathogenesis of chronic spontaneous urticaria (CSU). To date, association of IgE and IgG AAbs with Chinese CSU patients has not been fully investigated. We aimed to explore prevalence rates of IgE and IgG AAbs in Chinese CSU patients and their association with clinical and laboratory parameters. Serum IgE and IgG AAbs against thyroid peroxidase (TPO) and thyroglobulin (TG), total IgE (tIgE) and specific IgEs were measured using enzyme-linked immunosorbent assay, chemiluminescence microparticle immunoassay and immunoblotting. Meta-analyses and literature review were conducted. The meta-analyses indicated that CSU cases were 4.98, 6.90 and 6.68 times more likely to have positive anti-TPO IgE, anti-TPO IgG and anti-TG IgG (all P < 0.001) compared with controls, respectively, and revealed a positive correlation between the prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.53, P = 0.025). A total of 1,100 Chinese Han adult CSU patients and 1,100 ethnicity-, age- and sex-matched healthy controls were recruited from 15 centers. Prevalence rates of anti-TPO IgE, anti-TPO IgG, anti-TG IgE or anti-TG IgG in the patients were all significantly higher than those in the controls. Significant correlations were observed between prevalence rates of anti-TPO IgE and anti-TPO IgG (r = 0.297, P < 0.001) as well as between those of anti-TG IgE and anti-TG IgG in the patients (r = 0.137, P < 0.001). Patients with anti-TPO IgE or anti-TPO IgG had significantly lower tIgE levels (P < 0.001). Positive anti-TPO IgE, positive anti-TPO IgG and tIgE < 40 IU/mL were independent predictors of antihistamine-refractory cases. In conclusion, the prevalence rates of IgE and IgG AAbs in Chinese CSU patients are significantly elevated and reciprocally correlated. This study verifies the results of previous case-control studies of CSU patients from other populations and ethnicities.

20.
Front Immunol ; 12: 681714, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34539625

RESUMEN

Background: Chronic spontaneous urticaria (CSU) is a common autoimmune skin disease. Little is known about the role of epigenetics in the pathogenesis of CSU. This study aimed to investigate genome-wide DNA methylation profile in whole blood of patients with CSU. Patients and Methods: Genome-wide DNA methylation levels in whole blood samples of 95 Chinese Han ethnicity adult CSU patients and 95 ethnicity-, age- and sex-matched healthy controls were analyzed using Illumina 850K methylation chip. The differentially methylated genes (DMGs) were screened out and then functionally annotated by the gene ontology and the Kyoto encyclopedia of genes and genomes databases. Results: A total of 439 differentially methylated positions (DMPs) (p < 0.01 and |Δß| ≥ 0.06) were identified with 380 hypomethylated and 59 hypermethylated. The average global DNA methylation levels of the 439 DMPs in the CSU patients were significantly lower than those in the healthy controls (p < 0.001). The distribution of the 439 DMPs was wide on chromosome 1 to 22 and chromosome X. Chromosome 6 embodied the largest number of DMPs (n = 51) and their annotated genes were predominantly related to autoimmunity. The 304 annotated DMGs were mainly enriched in autoimmune disease- and immune-related pathways. A total of 41 DMPs annotated to 28 DMGs were identified when p < 0.01 and |Δß| ≥ 0.1. Of the 28 DMGs, HLA-DPB2, HLA-DRB1, PPP2R5C, and LTF were associated with autoimmunity. CSU cases with elevated total IgE, positive anti-thyroid peroxidase IgG autoantibodies, positive anti-thyroglobulin IgG autoantibodies, angioedema, UASday > 4, or recurrent CSU showed phenotype-specific DMPs as compared with cases with normal total IgE, negative anti-thyroid peroxidase IgG autoantibodies, negative anti-thyroglobulin IgG autoantibodies, no angioedema, UASday ≤ 4, or non-recurrent CSU respectively. Conclusion: This study shows a distinct genome-wide DNA methylation profile in Chinese Han ethnicity adult CSU patients and indicates a role of epigenetics in the pathogenesis of CSU. The predominant enrichment of the CSU-associated DMGs in immunological pathways provides supportive evidence for the immunopathogenesis of CSU. Future research on the CSU-associated DMPs and DMGs will help discover potential therapeutic targets for CSU.


Asunto(s)
Urticaria Crónica/etiología , Metilación de ADN , Epigénesis Genética , Transcriptoma , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Autoinmunidad , Estudios de Casos y Controles , Urticaria Crónica/diagnóstico , Biología Computacional/métodos , Islas de CpG , Susceptibilidad a Enfermedades/inmunología , Perfilación de la Expresión Génica , Ontología de Genes , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología
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