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1.
Diabetol Metab Syndr ; 15(1): 235, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978556

RESUMEN

Bile acids, which are steroid molecules originating from cholesterol and synthesized in the liver, play a pivotal role in regulating glucose metabolism and maintaining energy balance. Upon release into the intestine alongside bile, they activate various nuclear and membrane receptors, influencing crucial processes. These bile acids have emerged as significant contributors to managing type 2 diabetes mellitus, a complex clinical syndrome primarily driven by insulin resistance. Bile acids substantially lower blood glucose levels through multiple pathways: BA-FXR-SHP, BA-FXR-FGFR15/19, BA-TGR5-GLP-1, and BA-TGR5-cAMP. They also impact blood glucose regulation by influencing intestinal flora, endoplasmic reticulum stress, and bitter taste receptors. Collectively, these regulatory mechanisms enhance insulin sensitivity, stimulate insulin secretion, and boost energy expenditure. This review aims to comprehensively explore the interplay between bile acid metabolism and T2DM, focusing on primary regulatory pathways. By examining the latest advancements in our understanding of these interactions, we aim to illuminate potential therapeutic strategies and identify areas for future research. Additionally, this review critically assesses current research limitations to contribute to the effective management of T2DM.

2.
J Sep Sci ; 46(17): e2300164, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37387568

RESUMEN

Accurate quantitative analysis of trace analytes in a complicated matrix is a challenge in modern analytical chemistry. An appropriate analytical method is considered to be one of the most common gaps during the whole process. In this study, a green and efficient strategy based on miniaturized matrix solid-phase dispersion and solid-phase extraction combined with capillary electrophoresis was first proposed for extracting, purifying and determining target analytes from complicated matrix, using Wubi Shanyao Pill as an example. In detail, 60 mg of samples were dispersed on MCM-48 to obtain high yields of analytes, then the extract was purified with a solid-phase extraction cartridge. Finally, four analytes in the purified sample solution were determined by capillary electrophoresis. The parameters affecting the extraction efficiency of matrix solid-phase dispersion, purification efficiency of solid-phase extraction and separation effect of capillary electrophoresis were investigated. Under the optimized conditions, all analytes demonstrated satisfactory linearity (R2 >0.9983). What's more, the superior green potential of the developed method for the determination of complex samples was confirmed by the Analytical GREEnness Metric Approach. The established method was successfully applied in the accurate determination of target analytes in Wubi Shanyao Pill and thus provided reliable, sensitive, and efficient strategy support for its quality control.


Asunto(s)
Electroforesis Capilar , Extracción en Fase Sólida , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión
3.
J Hazard Mater ; 456: 131717, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37245369

RESUMEN

Herein, L-cysteine (Cys) was modified on zero-valent iron (C-ZVIbm) by using a mechanical ball-milling method to improve the surface functionality and the Cr(VI) removal efficiency. Characterization results indicated that Cys was modified on the surface of ZVI by the specific adsorption of Cys on the oxide shell to form a -COO-Fe complex. The Cr(VI) removal efficiency of C-ZVIbm (99.6%) was much higher than that of ZVIbm (7.3%) in 30 min. The attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis inferred that Cr(VI) was more likely to be adsorbed on the surface of C-ZVIbm to form bidentate binuclear inner-sphere complexes. The adsorption process was well-matched to the Freundlich isotherm and the pseudo-second-order kinetic model. Electrochemical analysis and electron paramagnetic resonance (ESR) spectroscopy revealed that Cys on the C-ZVIbm lowered the redox potential of Fe(III)/Fe(II), and favored the surface Fe(III)/Fe(II) cycling mediated by the electrons from Fe0 core. These electron transfer processes were beneficial to the surface reduction of Cr(VI) to Cr(III). Our findings provide new understandings into the surface modification of ZVI with a low-molecular weight amino acid to promote in-situ Fe(III)/Fe(II) cycling, and have great potential for the construction of efficient systems for Cr(VI) removal.

4.
Environ Pollut ; 330: 121813, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37178952

RESUMEN

The widespread use of polychlorophenols poses enormous environmental challenges. Biochar has the potential to accelerate the transformation of polychlorophenols. But the biochar-triggered photochemical decomposition mechanism of polychlorophenols still remains unclear. Herein, the photochemical behavior of pyrochar was comprehensively investigated in 2,4,6-trichlorophenol (TCP) remediation. Researches revealed that persistent free radicals (PFRs) and oxygenated functional groups (OFGs) on the surface of pyrochar cooperatively promoted ROS generation for TCP degradation. PFRs performed a key role of electron-donating and energy transfer in ROS conversion, especially in the activation of H2O2 into •OH. The hydroxyl groups of photosensitive components of pyrochar were photo-excited and provided electrons for enhanced ROS formation as well. With photogenerated ROS involved, more TCP was decomposed through dechlorination under light irradiation than that in the dark, in which 1O2, •OH, and •O2- were the dominant active species. During this process, stronger light intensities (3 W/m2) and shorter light wavelengths (400 nm) can provide more energy for the activation of PFRs and OFGs, promoting the decomposition of TCP. This work casts a new light on the environmental roles of pyrochar in the photochemical removal of polychlorophenol pollutants.


Asunto(s)
Carbón Orgánico , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno , Peróxido de Hidrógeno/química , Carbón Orgánico/química , Radicales Libres/química
5.
Pest Manag Sci ; 79(4): 1273-1283, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36308727

RESUMEN

BACKGROUND: Fungicides play a significant role in the integrated management of plant pathogens. However, the irrational application of fungicides with similar structures has led to development of cross-resistance, therefore there is a need to seek novel fungicides with new structures. RESULTS: Twenty-eight novel sulfoximine derivatives incorporating nitroguanidine moieties were designed, synthesized, and evaluated as antifungal agents. The bioassay results indicated that most of the synthesized compounds displayed excellent fungicidal activities against Sclerotinia sclerotiorum, Rhizoctonia solani, Fusarium graminearum, and Pyricularia grisea. Among these, compounds 6c4 , 6c5 , and 6c6 exhibited remarkable fungicidal activities against P. grisea, with EC50 values of 1.28, 1.17, and 1.68 µg mL-1 , respectively. In addition, compound 6c2 displayed the most potent activity against S. sclerotiorum (EC50  = 3.64 µg mL-1 ). Further in vivo fungicidal activity screening against S. sclerotiorum demonstrated that the protective and curative effects of compound 6c2 were 98.1% and 91.3% at 25 µg mL-1 , respectively, comparable to that of boscalid (94.4%, 89.6%). The preliminary mechanism study found that the hyphae of S. sclerotiorum treated with compound 6c2 was abnormal with mycelial collapse and membrane permeability increase. The present findings can help to develop new fungicides for crop protection. CONCLUSION: Novel sulfoximine derivatives containing nitroguanidine possess potential antifungal activity, and the unique structure may offer an alternative option for fungicide development in the future. © 2022 Society of Chemical Industry.


Asunto(s)
Antifúngicos , Fungicidas Industriales , Antifúngicos/farmacología , Fungicidas Industriales/farmacología , Relación Estructura-Actividad , Guanidinas
6.
Drug Dev Ind Pharm ; 48(6): 255-264, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36026436

RESUMEN

Local analgesia is one of the most desirable methods for postoperative pain control, while the existing local anesthetics have a short duration of analgesic effect. Nano-drug carriers have been widely used in various fields and provide an excellent strategy for traditional drugs. Although the existing liposomes for local anesthetics have certain advantages, their instability and complexity of the preparation process still cannot be ignored. Here, we developed novel ropivacaine hydrochloride liposomes with improved stability and sustained release performance by combining ropivacaine hydrochloride with sodium oleate in liposomes via hydrophobic ion-pairing (HIP). The liposomes are easy to prepare, inexpensive, and suitable for mass production. The infrared (IR), particle size, and Zeta potential measurements adequately characterized the complex, which showed a diameter of 81.09 nm and a zeta potential of -83.3 mV. Animal behavioral experiments, including the hot plate test and von Frey fiber test, demonstrated that the liposome system had a prolonged analgesic effect of 2 h versus conventional liposome preparations, consistent with the results of in vitro release experiments. In addition, in vitro cytotoxicity evaluations in RAW264.7 cells and in vivo evaluations revealed the biocompatibility and safety of the ropivacaine-sodium oleate ion-paired liposome (Rop-Ole-Lipo) system as a suitable local anesthetic for local pain management. Our findings provide a new idea for the preparation of local anesthetics.


Asunto(s)
Anestésicos Locales , Liposomas , Analgésicos , Anestésicos Locales/química , Animales , Manejo del Dolor , Ropivacaína/química
7.
Plant Physiol ; 190(2): 1182-1198, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-35809074

RESUMEN

Cell wall lignification is a key step in forming functional endodermis and protoxylem (PX) in plant roots. Lignified casparian strips (CS) in endodermis and tracheary elements of PX are essential for selective absorption and transport of water and nutrients. Although multiple key regulators of CS and PX have been identified, the spatial information that drives the developmental shift to root lignification remains unknown. Here, we found that brassinosteroid (BR) signaling plays a key role in inhibiting root lignification in the root elongation zone. The inhibitory activity of BR signaling occurs partially through the direct binding of BRASSINAZOLE-RESISTANT 1 (BZR1) to SHORT-ROOT (SHR), repressing the SHR-mediated activation of downstream genes that are involved in root lignification. Upon entering the mature root zone, BR signaling declines rapidly, which releases SHR activity and initiates root lignification. Our results provide a mechanistic view of the developmental transition to cell wall lignification in Arabidopsis thaliana roots.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides/metabolismo , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Agua/metabolismo
8.
J Integr Plant Biol ; 64(4): 859-870, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35199475

RESUMEN

Root cap not only protects root meristem, but also detects and transduces the signals of environmental changes to affect root development. The symplastic communication is an important way for plants to transduce signals to coordinate the development and physiology in response to the changing enviroments. However, it is unclear how the symplastic communication between root cap cells affects root growth. Here we exploit an inducible system to specifically block the symplastic communication in the root cap. Transient blockage of plasmodesmata (PD) in differentiated collumella cells severely impairs the root development in Arabidopsis, in particular in the stem cell niche and the proximal meristem. The neighboring stem cell niche is the region that is most sensitive to the disrupted symplastic communication and responds rapidly via the alteration of auxin distribution. In the later stage, the cell division in proximal meristem is inhibited, presumably due to the reduced auxin level in the root cap. Our results reveal the essential role of the differentiated collumella cells in the root cap mediated signaling system that directs root development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Meristema , Raíces de Plantas
9.
Environ Res ; 195: 110880, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33607096

RESUMEN

Artificial photoreduction of CO2 to clean energy utilizing the unlimited solar energy has shown promise to suppress the greenhouse effect and alleviate the energy shortage. In this study, a simple one-step calcination method was utilized to synthesize ultrathin nanosheet g-C3N4 (NS-g-C3N4). The prepared NS-g-C3N4 with a thickness of 10 nm was demonstrated to exhibited higher efficiency and selectivity than that of bulk counterpart (B-g-C3N4) for the photocatalytic reduction of CO2 to CO under visible light irradiation. The yield of CO in the system with obtained NS-g-C3N4 was 5.8 times higher than that of B-g-C3N4. CO was measured to be the sole product detected in the system with NS-g-C3N4, while CO2 can be reduced into CO, CH4 and CH3OH in the system with B-g-C3N4 under the same photocatalytic reduction conditions. The ultrathin nanostructures and abundant surface defect sites of NS-g-C3N4 could enhance the visible light adsorption efficiency, favor the separation and transfer of photogenerated carriers, and provide strong chemisorption sites for CO2, and thus resulting in its remarkable photocatalytic activity to CO2 reduction. More importantly, the surface defects of nanosheet could shift the adsorption mode of CO2 from N-CO2- for the B-g-C3N4 to N-O-CO for NS-g-C3N4, and eventually contributing the selective photoreduction of CO2 to CO. The obtained also NS-g-C3N4 exhibited excellent stability for CO2 photoreduction. No significant change in the photoreduction efficiency of CO2 in the system with NS-g-C3N4 was observed after four cycles. This study could not only provide a novel strategy to realize the high selectivity and efficiency photocatalytic conversion CO2 to CO, but also aims to clarify the interactions between the adsorption model of CO2 on g-C3N4 surface and the selectivity and efficiency of CO2 photoreduction.


Asunto(s)
Dióxido de Carbono , Nanoestructuras , Adsorción , Catálisis , Luz
10.
Ecotoxicol Environ Saf ; 211: 111950, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33493723

RESUMEN

Recently, fragrance ingredients have attracted increasing attention due to their imperceptible risks accompanying the comfortable feeling. To understand transformation mechanisms and toxicity evolution of benzyl formate (BF) in environment, its photochemical degradation in water was thoroughly studied herein. Results showed that 83.5% BF was degraded under ultraviolet (UV) irradiation for 30 min. Laser flash photolysis and quenching experiments demonstrated that triplet excited state (3BF*), O2•-, and 1O2 were three main reactive species found during BF photodegradation. Eight degradation intermediates, including benzaldehyde, benzyl alcohol, o-cresol, bibenzyl, benzyl ether, 1,2-diphenylethanol, benzoic acid, and benzylhemiformal, were mainly formed as identified by LC-Q-TOF/MS and GC-MS analyses. Furthermore, the degradation mechanism was explained as the bond cleavage of 3BF* and BF•+, O2•-/1O2 oxidation, eaq- reduction, and •OH addition reactions. Aquatic assessment suggests that except benzyl alcohol, benzoic acid, and benzylhemiformal, all the products were persistent and could result in increased aquatic toxicity compared to original BF. Consequently, these degradation products may cause more toxicity to organisms if they remain accumulated in water environment for a long time.


Asunto(s)
Formiatos/toxicidad , Procesos Fotoquímicos , Contaminantes Químicos del Agua/toxicidad , Cinética , Luz , Odorantes , Perfumes , Fotólisis , Rayos Ultravioleta , Agua/química , Contaminantes Químicos del Agua/química
11.
Water Res ; 176: 115745, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32234607

RESUMEN

Widespread occurrence of emerging organic contaminants (EOCs) in water have been explicitly associated with adverse effects on human health, therefore representing a major risk to public health. Especially the increased toxicity is frequently observed during the photodegradation of EOCs in natural water, and even wastewater treatment plants. However, the culprit of increased toxicity and formation mechanism has yet to be recognized regarding the estrogenic activity. In this study, by combining laboratory experiments with quantum chemical calculations, the induction of human estrogenic activity was investigated using the yeast two-hybrid reporter assay during the photodegradation of preservatives ethylparaben (EP), along with identification of toxic products and formation mechanisms. Results showed that the increase in estrogenic effect was induced by photochemically generated oligomers, rather than the expected OH-adduct. The maximum estrogenic activity corresponded to the major formation of oligomers, while OH-adducts were less than 12%. Two photochemically generated oligomers were found to contribute to estrogenic activity, produced from the cleavage of excited triplet state molecules and subsequent radical-radical reactions. Computational toxicology results showed that the increased estrogenic activity was attributed to oligomer [4-Hydroxy-isophthalic acid 1-ethyl ester 3-(4-hydroxy-phenyl)] and its EC50 was lower than that of the parent EP. In contrast, OH-adducts exhibited higher EC50 values than the parent EP, while still possessing estrogenic activity. Therefore, more attention should be paid to these photodegradation products of EOCs, including OH-adducts.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Estrógenos , Humanos , Parabenos , Fotólisis
12.
J Integr Plant Biol ; 62(7): 897-911, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31638324

RESUMEN

Root stem cell niche (SCN) consists of a quiescent center (QC) and surrounding stem cells. Disrupted symplastic communication leads to loss of stemness in the whole SCN. Several SCN regulators were reported to move between cells for SCN maintenance. However, single mutant of these regulators is insufficient to abolish QC stemness despite the high differentiation rate in surrounding stem cells. To dissect the mechanism behind such distinct stemness in SCN, we combined the mis-expression strategy with pWOX5:icals3m system in which QC is symplastically isolated. We found the starch accumulation in QC could be synergistically repressed by WUSCHEL-RELATED HOMEOBOX 5 (WOX5), SHORT-ROOT (SHR), SCARCROW (SCR), and PLETHORA (PLT). Like PLTs, other core regulators also exhibited dimorphic functions by inhibiting differentiation at a higher dose while promoting cell division at a low protein level. Being located in the center of the intersected expression zones, QC cells receive the highest level of core regulators, forming the most robust stemness within SCN. WUSCHEL-RELATED HOMEOBOX 5 was sufficient to activate PLT1/2 expression, contributing to the QC-enriched PLTs. Our results provide experimental evidence supporting the long-standing hypothesis that the combination of spatial expression, synergistic function and dosage effect of core regulators result in spatially distinct stemness in SCN.


Asunto(s)
Arabidopsis/citología , Arabidopsis/metabolismo , Meristema/citología , Meristema/genética , Nicho de Células Madre/genética , Células Madre/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Arabidopsis/metabolismo , Ciclo Celular/genética , Prueba de Complementación Genética , Modelos Biológicos , Mutación/genética , Plantas Modificadas Genéticamente , Células Madre/citología
13.
Environ Int ; 129: 68-75, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31121517

RESUMEN

The ubiquitous presence of fragrance-associated synthetic musk is cause for serious concern due to their transformation and environmental impacts. In particular, nitro-musks are frequently detected in various matrices, including water, even though they were restricted because of carcinogenicity. Thus, using musk xylene as a model compound, the mechanism, eco-toxicity and health effects during OH-initiated transformation process were systematically studied using quantum chemistry and computational toxicology. Results indicate that musk xylene can be exclusively transformed via H-abstraction pathways from its methyl group, with total rate constants of 5.65 × 108-8.79 × 109 M-1 s-1, while the contribution of other pathways, including single-electron transfer and OH-addition pathways, were insignificant. The subsequent dehydrogenation intermediates (MX(H)) could further transform into cyclic, aldehyde and demethylation products. Based on toxicity assessments, all the transformation products exhibited decreased aquatic toxicity to fish in comparison with the parent musk xylene but they were still classified at toxic or very toxic levels, especially the cyclic products. More importantly, these products still exhibited carcinogenic activity during OH-initiated transformation and increased carcinogenicity relative to the parent musk xylene. This is the first time that the transformation mechanism and environmental impacts of nitro-musks have been explored through theoretical calculations.


Asunto(s)
Peces/metabolismo , Contaminantes Químicos del Agua/toxicidad , Xilenos/toxicidad , Animales , Biología Computacional , Ecotoxicología , Odorantes , Perfumes/toxicidad , Procesos Fotoquímicos
14.
Environ Pollut ; 247: 362-370, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30690232

RESUMEN

Short chain chlorinated paraffins (SCCPs) have attracted worldwide attention in recent years, due to their high production volume, persistent, bioaccumulative and toxic properties. In this study, 1-chlorodecane (CD) was selected as a model of SCCPs to explore its photochemical degradation behavior under UV irradiation. The results found that CD could be completely photochemical degradation within 120 min, and the •OH was found to be the main reactive species from both quenching experiments and electron paramagnetic resonance (EPR) results. However, the contribution of triple excited state of CD (3CD*) was still nonnegligible from the results with the absorption peak at 480 nm obtained by laser flash photolysis. Based on the identified intermediates as well as the data from theoretical chemical calculation, the detailed photochemical degradation mechanism of CD was tentatively proposed that CD firstly was excited and photo-ionized under UV irradiation, and the released Cl• in water could result in generating •OH. Then •OH initiates CD degradation mainly through the H-abstraction pathway, leading to the generation of several dehydrogenation radicals, which further generated alcohols or long chain intermediates through radical-radical reactions. The results will provide a comprehensive understanding of the degradation mechanism and environmental fates of SCCPs in water under UV irradiation.


Asunto(s)
Hidrocarburos Clorados/química , Procesos Fotoquímicos , Contaminantes Químicos del Agua/química , Cinética , Luz , Modelos Químicos , Parafina/química , Fotólisis , Rayos Ultravioleta , Agua
15.
Water Res ; 137: 130-143, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29547776

RESUMEN

With the increased concentrations and kinds of refractory organic contaminants (ROCs) in aquatic environments, many previous reviews systematically summarized the applications of carbon-based materials in the adsorption and catalytic degradation of ROCs for their economically viable and environmentally friendly behavior. Interestingly, recent studies indicated that carbon-based materials in natural environment can also mediate the transformation of ROCs directly or indirectly due to their abundant persistent free radicals (PFRs). Understanding the formation mechanisms of PFRs in carbo-based materials and their interactions with ROCs is essential to develop their further applications in environment remediation. However, there is no comprehensive review so far about the direct and indirect removal of ROCs mediated by PFRs in amorphous, porous and crystalline carbon-based materials. The review aims to evaluate the formation mechanisms of PFRs in carbon-based materials synthesized through pyrolysis and hydrothermal carbonization processes. The influence of synthesis conditions (temperature and time) and carbon sources on the types as well as the concentrations of PFRs in carbon-based materials are also discussed. In particular, the effects of metals on the concentrations and types of PFRs in carbon-based materials are highlighted because they are considered as the catalysts for the formation of PFRs. The formation mechanisms of reactive species and the further transformation mechanisms of ROCs are briefly summarized, and the surface properties of carbon-based materials including surface area, types and number of functional groups, etc. are found to be the key parameters controlling their activities. However, due to diversity and complexity of carbon-based materials, the exact relationships between the activities of carbon-based materials and PFRs are still uncertain. Finally, the existing problems and current challenges for the ROCs transformation with carbon-based materials are also pointed out.


Asunto(s)
Carbono/química , Radicales Libres/química , Contaminantes del Agua/química , Restauración y Remediación Ambiental , Purificación del Agua
16.
ACS Appl Mater Interfaces ; 9(20): 17115-17124, 2017 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-28467036

RESUMEN

As Fenton systems suffer from the undesirable Fe(III)/Fe(II) cycle, great efforts were made to realize the effective reduction of Fe(III) to Fe(II). The effects of hydrothermal carbon (HTC) on the Fe(III)/H2O2 Fenton-like reaction and the subsequent degradation of alachlor in water was systematically investigated, and the results indicated that HTC could enhance alachlor degradation in Fe(III)/H2O2 by promoting the Fe(III)/Fe(II) cycle via electron transfer from HTC to Fe(III) ions. The apparent alachlor degradation rate constant in the HTC-G/Fe(III)/H2O2 system (7.02 × 10-2 min-1) was about 3 times higher than that in the Fe(III)/H2O2 system (2.25 × 10-2 min-1). The electron spin resonance spectra analysis revealed that HTC consists of abundant carbon-centered persistent free radicals to act as the electron donor. Meanwhile, the hydroxyl groups on the surface of HTC also played an important role in the enhanced alachlor degradation because the decrease in the surface hydroxyl groups on HTC significantly decreased the degradation of alachlor. On the basis of these results, an Fe(III) complex with surface hydroxyl groups on HTC was proposed to favor the electron transfer from the hydroxyl groups to Fe(III), and then, the simultaneously produced Fe(II) could accelerate the catalytic decomposition of H2O2 to facilitate alachlor degradation. These findings shed new light on the possible roles of carbon materials in a natural aquatic environment and provide a new pathway for environmental pollutant control and remediation of organic contaminants by HTC.

17.
Neurol Sci ; 38(7): 1241-1247, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28417215

RESUMEN

Investigating hippocampal subfields may provide new and important insights into the pathophysiology of posttraumatic stress disorder (PTSD). However, no study has examined the hippocampal subfield volume changes in parents with or without PTSD who had lost their only child and could no longer conceive in China. Fifty-seven parents with PTSD (PTSD+), 11 trauma-exposed parents without PTSD (PTSD-), and 39 non-traumatized controls were recruited to examine the hippocampal subfield volumes using magnetic resonance imaging. Correlations of the volumes with the time since trauma and Clinician-Administered PTSD Scale (CAPS) scores were investigated in the PTSD+ group. The volumes of the bilateral cornu ammonis (CA) 2-3, CA4-dentate gyrus (DG), and left subiculum were significantly smaller in the PTSD+ and PTSD- groups than in the controls, but there were no significant differences between the PTSD+ and PTSD- groups. Additionally, the left CA2-3 and CA4-DG volumes reduced more than those on the right side in the PTSD+ and PTSD- groups. The subfield volumes were not related to the time since trauma and the CAPS scores in the PTSD+ group. In conclusion, hippocampal subfield volumes decreased in parents who lost their only child with or without PTSD, and the volumetric reduction may be independent of PTSD and trauma-related. Moreover, the hippocampal volume deficits showed laterality that the left side was affected more than the right, and the hippocampal subfields may show differential vulnerabilities to trauma/PTSD, with the CA2-3 and CA4-DG subfields more sensitive than others.


Asunto(s)
Hipocampo/patología , Hijo Único/psicología , Padres/psicología , Trastornos por Estrés Postraumático/patología , Adulto , Anciano , Atrofia , Trastorno Bipolar/patología , Giro Dentado/patología , Femenino , Lateralidad Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/fisiología , Lóbulo Temporal/patología
18.
Environ Sci Technol ; 49(13): 7948-56, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26066010

RESUMEN

In this study, we demonstrate that protocatechuic acid (PCA) can significantly promote the alachlor degradation in the Fe(III)/H2O2 Fenton oxidation system. It was found that the addition of protocatechuic acid could increase the alachlor degradation rate by 10 000 times in this Fenton oxidation system at pH = 3.6. This dramatic enhancement of alachlor degradation was attributed to the complexing and reduction abilities of protocatechuic ligand, which could form stable complexes with ferric ions to prevent their precipitation and also accelerate the Fe(III)/Fe(II) cycle to enhance the ·OH generation. Meanwhile, the Fe(III)/PCA/H2O2 system could also work well at near natural pH even in the case of PCA concentration as low as 0.1 mmol/L. More importantly, both alachlor and PCA could be effectively mineralized in this Fenton system, suggesting the environmental benignity of PCA/Fe(III)/H2O2 Fenton system. We employed gas chromatography-mass spectrometry to identify the degradation intermediates of alachlor and then proposed a possible alachlor degradation mechanism in this novel Fenton oxidation system. This study provides an efficient way to remove chloroacetanilide herbicides, and also shed new insight into the possible roles of widely existed phenolic acids in the conversion and the mineralization of organic contaminants in natural aquatic environment.


Asunto(s)
Acetamidas/química , Peróxido de Hidrógeno/química , Hidroxibenzoatos/química , Hierro/química , Carbono/aislamiento & purificación , Cloruros/análisis , Ambiente , Compuestos Férricos/química , Iones , Factores de Tiempo
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