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1.
Gut ; 73(7): 1183-1198, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38621924

RESUMEN

OBJECTIVE: Targeting bacterial translocation in cirrhosis is limited to antibiotics with risk of antimicrobial resistance. This study explored the therapeutic potential of a non-absorbable, gut-restricted, engineered carbon bead adsorbent, Yaq-001 in models of cirrhosis and acute-on-chronic liver failure (ACLF) and, its safety and tolerability in a clinical trial in cirrhosis. DESIGN: Performance of Yaq-001 was evaluated in vitro. Two-rat models of cirrhosis and ACLF, (4 weeks, bile duct ligation with or without lipopolysaccharide), receiving Yaq-001 for 2 weeks; and two-mouse models of cirrhosis (6-week and 12-week carbon tetrachloride (CCl4)) receiving Yaq-001 for 6 weeks were studied. Organ and immune function, gut permeability, transcriptomics, microbiome composition and metabolomics were analysed. The effect of faecal water on gut permeability from animal models was evaluated on intestinal organoids. A multicentre, double-blind, randomised, placebo-controlled clinical trial in 28 patients with cirrhosis, administered 4 gr/day Yaq-001 for 3 months was performed. RESULTS: Yaq-001 exhibited rapid adsorption kinetics for endotoxin. In vivo, Yaq-001 reduced liver injury, progression of fibrosis, portal hypertension, renal dysfunction and mortality of ACLF animals significantly. Significant impact on severity of endotoxaemia, hyperammonaemia, liver cell death, systemic inflammation and organ transcriptomics with variable modulation of inflammation, cell death and senescence in the liver, kidneys, brain and colon was observed. Yaq-001 reduced gut permeability in the organoids and impacted positively on the microbiome composition and metabolism. Yaq-001 regulated as a device met its primary endpoint of safety and tolerability in the clinical trial. CONCLUSIONS: This study provides strong preclinical rationale and safety in patients with cirrhosis to allow clinical translation. TRIAL REGISTRATION NUMBER: NCT03202498.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Microbioma Gastrointestinal , Cirrosis Hepática , Humanos , Animales , Cirrosis Hepática/complicaciones , Ratones , Masculino , Microbioma Gastrointestinal/efectos de los fármacos , Método Doble Ciego , Ratas , Modelos Animales de Enfermedad , Femenino , Persona de Mediana Edad , Traslocación Bacteriana/efectos de los fármacos , Carbono/uso terapéutico , Carbono/farmacología
2.
Chin J Traumatol ; 27(1): 1-10, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38065706

RESUMEN

Programmed cell death 1 ligand 1 (PD-L1) is an important immunosuppressive molecule, which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1. The PD-L1 expression disorder plays an important role in the occurrence, development, and treatment of sepsis or other inflammatory diseases, and has become an important target for the treatment of these diseases. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with multiple differentiation potential. In recent years, MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases. Moreover, PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases. In this review, we will summarize the main regulatory mechanism of PD-L1 expression, and discuss various biological functions of PD-L1 in the immune regulation of MSCs.


Asunto(s)
Antígeno B7-H1 , Inmunomodulación , Células Madre Mesenquimatosas , Humanos , Antígeno B7-H1/metabolismo , Células Madre Mesenquimatosas/inmunología , Linfocitos T/metabolismo
3.
Environ Sci Technol ; 57(19): 7442-7453, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37144860

RESUMEN

Some contemporary aqueous film-forming foams (AFFFs) contain n:3 and n:1:2 fluorotelomer betaines (FTBs), which are often detected at sites impacted by AFFFs. As new chemical replacements, little is known about their environmental fate. For the first time, we investigated the biotransformation potential of 5:3 and 5:1:2 FTBs and a commercial AFFF that mainly contains n:3 and n:1:2 FTBs (n = 5, 7, 9, 11, and 13). Although some polyfluoroalkyl compounds are precursors to perfluoroalkyl acids, 5:3 and 5:1:2 FTBs exhibited high persistence, with no significant changes even after 120 days of incubation. While the degradation of 5:3 FTB into suspected products such as fluorotelomer acids or perfluoroalkyl carboxylic acids (PFCAs) could not be conclusively confirmed, we did identify a potential biotransformation product, 5:3 fluorotelomer methylamine. Similarly, 5:1:2 FTB did not break down or produce short-chain hydrogen-substituted polyfluoroalkyl acids (n:2 H-FTCA), hydrogen-substituted PFCA (2H-PFCA), or any other products. Incubating the AFFF in four soils with differing properties and microbial communities resulted in 0.023-0.25 mol % PFCAs by day 120. Most of the products are believed to be derived from n:2 fluorotelomers, minor components of the AFFF. Therefore, the findings of the study cannot be fully explained by the current understanding of structure-biodegradability relationships.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Betaína , Suelo , Contaminantes Químicos del Agua/análisis , Fluorocarburos/análisis , Agua , Ácidos Carboxílicos/metabolismo
4.
Exp Cell Res ; 410(1): 112955, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34875217

RESUMEN

The retinal pigment epithelium cells (RPE) are sensitive to oxidative stimuli due to long-term exposure to various environmental stimuli. Thus, the oxidative injury of RPE cells caused by the imbalance of redox homeostasis is one of the main pathogenic factors of age-related macular degeneration (AMD). But the sophisticated mechanisms linking AMD to oxidative stress are not fully elucidated. Activation of Nrf2 signal pathway can protect RPE cells from oxidative damage. The present study investigated the regulating mechanism of miR-125b in Nrf2 cascade and evaluated its antioxidant capacity. The in vitro studies indicated that overexpression of miR-125b substantially inhibited Keap1 expression, enhanced Nrf2 expression and induced Nrf2 nuclear translocation. Importantly, functional studies demonstrated that forced expression of miR-125b could significantly elevate cell proliferation and superoxide dismutase (SOD) levels while reduce reactive oxygen species (ROS) overproduction and malondialdehyde (MDA) formation. Further studies showed that miR-125b had no effect when Nrf2 was silenced in ARPE-19 cells. Additionally, the results identified that Nrf2 silence induced ROS accumulation enhances HIF-1α protein expression, while miR-125b could offset this effect via promoting HIF-1α protein degradation. Subsequent in vivo studies demonstrated that sodium iodate induced outer retina thinner was reversed with exogenous supplementation of miR-125b, which was cancelled in Nrf2 knockout mice. In conclusion, this study illustrated that miR-125b can protect RPE from oxidative damage via targeting Nrf2/HIF-1α signal pathway and potentially may serve as a therapeutic agent of AMD.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Degeneración Macular/genética , MicroARNs/genética , Factor 2 Relacionado con NF-E2/genética , Regulación de la Expresión Génica/genética , Humanos , Degeneración Macular/metabolismo , Degeneración Macular/patología , Estrés Oxidativo/genética , Especies Reactivas de Oxígeno/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Transducción de Señal
5.
Clin Exp Pharmacol Physiol ; 50(6): 476-485, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36802241

RESUMEN

Oxidative stress plays a major role in age-related cataract development. The cellular antioxidant protein thioredoxin-1 (Trx-1) and its negative regulator, thioredoxin binding protein-2 (TBP-2), are pivotal in the cellular redox balance during oxidative stress. The aim of this study is to investigate the effect of Trx-1 and TBP-2 on LC3 I/LC3 II in oxidative stress-induced autophagy in human lens epithelial cells (LECs). In our study, LECs were treated with 50 µM H2 O2 for different durations, and the expression of Trx-1 and TBP-2 were measured by RT-PCR and Western blot. Trx-1 activity was evaluated by the thioredoxin activity fluorescent assay. The subcellular localization of Trx-1 and TBP-2 was evaluated by cellular immunofluorescence. The interaction between Trx-1 and TBP-2 was examined by co-immunoprecipitation. The cell viability was detected using CCK-8, and the expression of LC3-II/LC3-I was detected to evaluate the autophagy. The results showed that the mRNA levels of the Trx-1 and TBP-2 were kinetically changed after treatment with H2 O2 for different durations. Exposure to H2 O2 increased the expression of TBP-2 but not Trx-1, while the exposure inhibited Trx-1 activity. TBP-2 was co-localized with Trx-1, and exposure to H2 O2 increased the interaction between TBP-2 and Trx-1. Trx-1 overexpression enhanced the autophagic response under normal circumstances and it might regulate autophagy in the initial phase. This study demonstrates the differential role of Trx-1 in cellular oxidative stress response, oxidative stress increased Trx-1 interaction with TBP-2, and Trx-1/TBP-2 regulated the autophagic response in the initial phase through LC3-II.


Asunto(s)
Células Epiteliales , Estrés Oxidativo , Humanos , Oxidación-Reducción , Células Epiteliales/metabolismo , Autofagia , Tiorredoxinas
6.
J Acoust Soc Am ; 153(3): 1612, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37002068

RESUMEN

This paper describes the study of the acoustic field of a fluid-filled pipe subjected to axial stress based on the acoustoelastic theory. The pipe with applied axial stresses can be approximated as a transversely isotropic pipe, and hence, its acoustic fields can be expressed using potential functions. The velocity changes of longitudinal wave modes with applied stresses are analyzed for the pipe filled with oil by an analytical method. It was found that the longitudinal mode velocity changes almost uniformly with the applied stresses. The high speed and low frequency plateaus of longitudinal wave modes are sensitive to stress. The relationship between stress and the velocity change of the guided wave is given. The results indicate that non-destructive testing techniques using longitudinal wave modes have strong potential to identify and monitor the stress levels in pipe structures.

7.
J Fish Biol ; 102(2): 349-357, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36317548

RESUMEN

Anti-lipopolysaccharide factors (ALFs) are small basic proteins that exhibit broad-spectrum antiviral properties and antibacterial activity. In this research, we cloned and studied two Eriocheir hepuensis ALFs, EhALF2 and EhALF3. The results showed that the open reading frame lengths of EhALF2 and EhALF3 were 363 and 372 bp, encoding 120 and 123 amino acids, respectively. Their sequences both contained an Lipopolysaccharide-binding (LPS) domain and were highly similarity to other crab ALFs. qRT-PCR showed that EhALF2 and EhALF3 were detected in nine examined tissues and were expressed the highest in the haemocytes. After challenge with Vibrio alginolyticus, in the hepatopancreas, the expression levels of EhALF2 and EhALF3 reached the highest levels at 48 and 3 h, respectively. In the heart, the expression levels of the two genes were highest at 12 h. These results indicate that EhALF2 and EhALF3 could participate in the resistance of E. hepuensis to V. alginolyticus stress within a short time. They have potential applications in the study of environmental stress markers and disease-resistance factors in E. hepuensis.


Asunto(s)
Braquiuros , Animales , Braquiuros/genética , Braquiuros/metabolismo , Vibrio alginolyticus/genética , Vibrio alginolyticus/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Lipopolisacáridos , Alineación de Secuencia , Clonación Molecular , Filogenia , Regulación de la Expresión Génica
8.
Anal Chem ; 94(19): 7115-7122, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35500042

RESUMEN

In this work, a novel methodology to design bifunctional ECL-luminophores with self-enhanced and TSA-amplified characteristics was proposed for improving the sensing performance of ECL-immunosensor toward trace cytokine analysis. Thanks to the qualitative- and quantitative- dual signal amplification technique, the as-prepared ECL biosensor demonstrated excellent detection performance. By analyzing the prospective cytokine biomarkers (IL-6), the ECL immunosensor exhibited a broad examination range with quite low detection limit and quite high selectivity, which was far superior to commercial ELISA kits and ever reported works. In particular, the novel ECL nanoprobe developed here could also be applied to monitor other immune toxicities or disease-related cytokines by using the respective antibodies corresponding to these targets. Moreover, the concept and construction strategy of self-amplified ECL-luminophores presented here could be further extended to design a series of Pdots-derived multicolored ECL probes to meet the needs of multipathway detection applications.


Asunto(s)
Técnicas Biosensibles , Técnicas Biosensibles/métodos , Citocinas , Técnicas Electroquímicas , Inmunoensayo/métodos , Límite de Detección , Mediciones Luminiscentes/métodos , Estudios Prospectivos
9.
Anal Chem ; 94(6): 2901-2911, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34989555

RESUMEN

Elucidating the intrinsic relationship between mitochondrial pH (pHm) fluctuation and lipid droplets (LDs) formation is vital in cell physiology. The development of small-molecular fluorescent probes for discrimination and simultaneous visualization of pHm fluctuation toward LDs has not yet been reported. In this work, utilizing pH-driven polarity-reversible hemicyanine and rhodamine derivatives, a multifunctional fluorescent probe is developed for selectively identifying mitochondria and LDs under specific pH values via dual-emission channels. This rapid-response probe, Hcy-Rh, has two distinct chemical structures under acidic and alkaline circumstances. In acidic conditions, Hcy-Rh exhibits good hydrophilicity that can target mitochondria and display an intense red fluorescence. Conversely, the probe becomes lipophilic under weakly alkaline conditions and targets LDs, showing a strong blue emission. In this manner, Hcy-Rh can selectively label mitochondria and LDs, exhibiting red and blue fluorescence, respectively. Moreover, this ratiometric probe is applied to map pHm changes in living cells under the stimulus with FCCP, NAC, and H2O2. The interplay of LD-mitochondria under oleic acid treatment and starvation-induced autophagy has been studied using this probe at different pH values. In a word, Hcy-Rh is a potential candidate for further exploring mitochondria-LD interaction mechanisms under pHm fluctuation. Moreover, the polarity-dependent strategy is valuable for designing other functional biological probes in imaging multiple organelles.


Asunto(s)
Colorantes Fluorescentes , Gotas Lipídicas , Colorantes Fluorescentes/química , Células HeLa , Humanos , Peróxido de Hidrógeno/análisis , Concentración de Iones de Hidrógeno , Gotas Lipídicas/metabolismo , Mitocondrias/química
10.
Environ Sci Technol ; 56(2): 885-895, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34967613

RESUMEN

The occurrence of 93 classes of per- and polyfluoroalkyl substances (PFASs) was investigated at aqueous film-forming foam (AFFF)-impacted sites of four Canadian airports. Surface/subsurface soil and groundwater samples were characterized using high-resolution mass spectrometry (HRMS) and an improved total oxidizable precursor (TOP) assay. PFAS profiles, loads, and spatial trends were highly site-specific, influenced by the AFFF use history, variations in sorption, transport, and in situ transformation potential of PFASs. All sites have been impacted by more than one AFFF chemistry, with the active firefighter training area exhibiting a greater PFAS variety and total PFAS burden than decommissioned sites. Zwitterionic and cationic compounds composed a large percentage (34.5-85.5%) of the total PFAS mass in most surface soil samples in the source zone but a relatively low percentage (<20%) in groundwater samples. Background soils surrounding the source zone contained predominantly unidentified precursors attributed to atmospheric deposition, while in AFFF-impacted soils, precursors originating from AFFFs can be largely captured by HRMS using available suspect lists. Horizontal transfer of PFASs in surface soils was limited, but vertical migration down the soil column occurred even in locations of low permeability. This study provides a critical data set to support developing new priority analyte lists and integrating TOP assay for comprehensive PFAS monitoring at AFFF-impacted sites.


Asunto(s)
Fluorocarburos , Agua Subterránea , Contaminantes Químicos del Agua , Aeropuertos , Canadá , Fluorocarburos/análisis , Agua Subterránea/química , Suelo , Agua , Contaminantes Químicos del Agua/análisis
11.
Environ Sci Technol ; 56(10): 6212-6222, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35533009

RESUMEN

Zwitterionic per- and polyfluoroalkyl substances are increasingly detected in aquatic environments. The magnitude of their concentration and increased frequency of detection worldwide raise questions on their presence in drinking water and associated health risk. Scientific knowledge on the identification of treatment technologies to effectively capture such zwitterionic PFAS from contaminated water sources remains largely unknown. In this study, we investigated the application of anionic organic scavenger ion exchange (IX) resins (A860), nonionic IX resins (XAD 4 and XAD 7), PFAS-specific resins (A694 and A592), and Ti3C2 MXenes (novel two-dimensional metal carbides) for the removal of select fluorotelomer zwitterionic PFAS from natural waters. The cumulative removal of zwitterionic PFAS at pH ∼ 7 follows the order: Ti3C2 MXenes > A694 > A592 > A860 > XAD 4 ∼ XAD 7. Ti3C2 MXenes were able to capture >75% of the total influent zwitterionic PFAS and the performance remained consistent in natural and synthetic water. Ti3C2 MXenes also exhibited efficient regeneration (>90% recovery) with 0.4 M Na2SO3 solution, while the regeneration efficacy of other IX resins generally remained below 20%. Treatment with ∼180 J/cm2 UV dosage in the 0.4 M Na2SO3 regenerant brine solution yielded >99.9% reduction in the zwitterionic PFAS concentration indicating that UV-sulfite systems exhibit promising potential for the treatment of zwitterionic PFAS concentrates.


Asunto(s)
Agua Potable , Fluorocarburos , Contaminantes Químicos del Agua , Aniones , Fluorocarburos/análisis , Intercambio Iónico , Contaminantes Químicos del Agua/análisis
12.
Environ Sci Technol ; 56(10): 6056-6068, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-34668380

RESUMEN

Zwitterionic, cationic, and anionic per- and polyfluoroalkyl substances (PFAS) are increasingly reported in terrestrial and aquatic environments, but their inputs to agricultural lands are not fully understood. Here, we characterized PFAS in 47 organic waste products (OWP) applied in agricultural fields of France, including historical and recent materials. Overall, 160 PFAS from 42 classes were detected from target screening and homologue-based nontarget screening. Target PFAS were low in agriculture-derived wastes such as pig slurry, poultry manure, or dairy cattle manure (median ∑46PFAS: 0.66 µg/kg dry matter). Higher PFAS levels were reported in urban and industrial wastes, paper mill sludge, sewage sludge, or residual household waste composts (median ∑46PFAS: 220 µg/kg). Historical municipal biosolids and composts (1976-1998) were dominated by perfluorooctanesulfonate (PFOS), N-ethyl perfluorooctanesulfonamido acetic acid (EtFOSAA), and cationic and zwitterionic electrochemical fluorination precursors to PFOS. Contemporaneous urban OWP (2009-2017) were rather dominated by zwitterionic fluorotelomers, which represented on average 55% of ∑160PFAS (max: 97%). The fluorotelomer sulfonamidopropyl betaines (X:2 FTSA-PrB, median: 110 µg/kg, max: 1300 µg/kg) were the emerging class with the highest occurrence and prevalence in contemporary urban OWP. They were also detected as early as 1985. The study informs for the first time that urban sludges and composts can be a significant repository of zwitterionic and cationic PFAS.


Asunto(s)
Compostaje , Fluorocarburos , Animales , Biosólidos , Bovinos , Estiércol , Aguas del Alcantarillado/química , Porcinos , Residuos
13.
J Acoust Soc Am ; 152(2): 765, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36050147

RESUMEN

In this paper, we construct a borehole model with an impermeable/permeable wall and study the seismoelectric responses. First, we define the boundary conditions at the borehole wall, then the acoustic field and electric field are simulated by the real axis integral method. In order to have a comprehensive analysis of the body wave components, we use the secant integral method to simulate the body waves and give the excitation intensity spectrum in the frequency domain. The results show that the impermeability of the borehole wall significantly increases the amplitude of the acoustic field generated by Stoneley waves. This is because the closed pores at the boundary make Stoneley waves energy leak more slowly and hence attenuating less. The impermeable borehole wall weakens the electromagnetic interface response. Besides, both P wave and S wave and their accompanying electric field properties are affected by boundary connectivity. This investigation provides a theoretical basis for qualitatively judging borehole wall permeability by the seismoelectric signals.

14.
J Psychosoc Oncol ; 40(4): 506-518, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34392806

RESUMEN

Purpose:Negative emotions can adversely affect the treatment and recovery of breast cancer patients. Post-traumatic stress caused by cancer can increase the negative emotions of patients. This study assessed the relationship between post-traumatic stress and emotional regulation strategies, and the role of emotional regulation in the relationship between post-traumatic stress and negative emotions in breast cancer patients.Design:Cross-sectional questionnaire with sample of 214 Chinese women with breast cancerMethods:Participants completed the Impact of Event Scale-Revised, Hospital Anxiety and Depression Scale, and Emotion Regulation Questionnaire. Correlation and mediation analyses were conducted to assess associations among the scores of these scales.Findings:Patients with low post-traumatic stress chose cognitive reappraisal strategies, while those with high post-traumatic stress chose expressive suppression strategies. Cognitive reappraisal had a significant negative predictive effect on negative emotions, while expressive suppression had a significant positive predictive effect on patient's negative emotions.Conclusions:Cognitive reappraisal may reduce the impact of post-traumatic stress on negative emotions experienced by breast cancer patients. Implications for psychosocial providers or policy: Psychosocial workers in China should conduct cognitive reappraisal training for breast cancer patients with high negative emotions and severe post-traumatic stress. For Chinese breast cancer patients living in other regions, the local oncology social workers should take into account their cultural background and lack of expression, and encourage them to choose cognitive reappraisal strategies.


Asunto(s)
Neoplasias de la Mama , Regulación Emocional , Trastornos por Estrés Postraumático , Neoplasias de la Mama/psicología , Neoplasias de la Mama/terapia , Cognición , Estudios Transversales , Emociones/fisiología , Femenino , Humanos
15.
Fish Shellfish Immunol ; 117: 228-239, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34418554

RESUMEN

Superoxide dismutase (SOD) can effectively eliminate of excess ROS, which causes oxidative damage to lipids, proteins, and DNA. In this study, we cloned the CuZn-SOD, cMn-SOD1, and cMn-SOD2 genes in Eriocheir hepuensis, and found that the coding sequence (CDS) lengths were 627 bp, 861 bp and 1062 bp, which encoded 208, 286, and 353 amino acids, respectively. Phylogenetic analysis indicated that all SOD genes were evolutionarily conserved, while cMn-SOD2 had an extra gap (67 amino acids) in the conserved domain compared with cMn-SOD1 without huge changes in the tertiary structure of the conserved domain, suggesting that cMn-SOD2 may be a duplicate of cMn-SOD1. qRT-PCR showed that the three SOD genes were widely expressed in all the tested tissues, CuZn-SOD and cMn-SOD1 were mostly expressed in the hepatopancreas, while cMn-SOD2 was mostly expressed in thoracic ganglia. Under azadirachtin stress, the oxidation index of surviving individuals, including the T-AOC, SOD activity, and MDA contents increased in the early stage and then remained steady except for a decrease in MDA contents in the later stage. qRT-PCR showed that the three SOD genes displayed the same trends as SOD activity in surviving individuals, and the highest expressions of CuZn-SOD in the hepatopancreas, heart, and gill were 14.16, 1.41, and 30.87 times that of the corresponding control group, respectively. The changes were 1.35, 5.77 and 3.33 fold for cMn-SOD1 and 1.62, 1.71 and 1.79 fold for cMn-SOD2, respectively. However, the activity and expression of SOD genes in dead individuals were lower than that observed in surviving individuals. These results reveal that SOD plays a significant role in the defence against azadirachtin-induced oxidative stress.


Asunto(s)
Proteínas de Artrópodos/genética , Braquiuros/genética , Insecticidas/toxicidad , Limoninas/toxicidad , Superóxido Dismutasa/genética , Animales , Femenino , Branquias/efectos de los fármacos , Branquias/metabolismo , Hepatopáncreas/efectos de los fármacos , Hepatopáncreas/metabolismo , Masculino , Miocardio/metabolismo , Estrés Fisiológico/genética
16.
Environ Sci Technol ; 55(24): 16655-16664, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34882405

RESUMEN

6:2 Fluorotelomer sulfonate (6:2 FTSA) is a ubiquitous environmental contaminant belonging to the family of per- and polyfluoroalkyl substances. Previous studies showed that hydroxyl radical (•OH) efficiently transforms 6:2 FTSA into perfluoroalkyl carboxylates (PFCAs) of different chain lengths (C2-C7), yet the reaction mechanisms were not elucidated. This study used density functional theory (DFT) calculations to map the entire reaction path of 6:2 FTSA initiated by •OH and experimentally verified the theoretical results. Optimal reaction pathways were obtained by comparing the rate constants calculated from the transition-state theory. We found that 6:2 FTSA was first transformed to C7 PFCA and C6F13•; C6F13• was then further reacted to C2-C6 PFCAs. The parallel addition of •OH and O2 to CnF2n+1• was essential to producing C2-C6 PFCAs. The critical step is the generation of alkoxyl radicals, which withdraw electrons from the adjacent C-C groups to result in chain cleavage. The validity of the calculated optimal reaction pathways was further confirmed by the consistency with our experimental data in the aspects of O2 involvement, identified intermediates, and the final PFCA profile. This study provides valuable insight into the transformation of polyfluoroalkyl substances containing aliphatic carbons in •OH-based oxidation processes.


Asunto(s)
Fluorocarburos , Radical Hidroxilo , Alcanosulfonatos , Teoría Funcional de la Densidad
17.
Environ Sci Technol ; 55(8): 4698-4708, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33739092

RESUMEN

Zwitterionic per- and polyfluoroalkyl substances (PFASs) used in aqueous film-forming foams (AFFFs) could face diverse environmental fates once released at military bases, airports, fire-training areas, and accidental release sites. Here, we studied for the first time the transformation potential of four electrochemical fluorination (ECF)-based PFAS zwitterions (two carboxyl betaines and two tertiary amines) in aerobic soils. The two perfluoroalkyl sulfonamide derivatives were precursors to perfluorooctanesulfonate (PFOS), while the amide derivatives were precursors to perfluorooctane carboxylate (PFOA). These zwitterions and four other previously reported zwitterions or cations were compared for their transformation pathways and kinetics. Structural differences, especially the nitrogen head groups, largely influenced the persistence of these compounds in aerobic soils. The perfluoroalkyl sulfonamide-based compounds showed higher microbial stability than the corresponding perfluoroalkyl amide-based ones. Their stability in aerobic soils is ranked based on the magnitude of DT50 (time for 50% of substance to disappear): quaternary ammonium ≈ carboxyl betaine ≫ tertiary amine > amine oxide. The PFASs containing quaternary ammonium or betaine groups showed high stability in soils, with the longest DT50 likely to be years or decades, while those with tertiary amine or amine oxide groups showed DT50 of weeks or months. These eight ECF-based precursors provide insights into the degradation pathways and persistence in surface soils of other perfluoroalkyl cations and zwitterions present in AFFFs.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes Químicos del Agua , Ácidos Carboxílicos , Fluorocarburos/análisis , Nitrógeno , Suelo , Agua , Contaminantes Químicos del Agua/análisis
18.
Environ Sci Technol ; 55(23): 16067-16077, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34751567

RESUMEN

Efficient destruction of perfluoroalkyl compounds in contaminated waters remains a challenge because of highly stable C-F bonds. In this study, mineralization of perfluorooctanoic acid (PFOA) with high concentration (∼30 mg/L) was realized in a needle-plate pulsed discharge reactor integrated with a water jet (NPDW) to which microbubbles (MBs) with different carrier gases (air, N2, and Ar) were introduced to enhance interfacial reactions. MBs effectively enrich dispersed PFOA from a bulk solution to a liquid surface to allow enhancing contact with reactive species and also expanding the plasma discharge area and channels. The PFOA removal efficiency in air and Ar discharge reached 81.5 and 95.3% in 2 h, respectively, with a defluorination ratio of no less than 50%. Energy requirements (EE/O) ranged from 216.49 to 331.95 kWh/m3. Aside from fluoride, PFOA was degraded to a range of short-chain perfluoroalkyl acids and, to a minor extent, at least 20 other fluorinated transformation products. PFOA degradation mechanisms were proposed, including decarboxylation, hydroxylation, hydrogenation reduction, and defluorination reactions. Real water matrices (groundwater, tap water, wastewater effluent, and surface water) showed moderate impact on treatment outcomes, demonstrating the robustness of the treatment process. The study demonstrated an environmentally friendly nonthermal plasma technology for effective PFOA degradation.


Asunto(s)
Fluorocarburos , Agua Subterránea , Contaminantes Químicos del Agua , Caprilatos , Microburbujas
19.
Exp Cell Res ; 387(1): 111748, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31785228

RESUMEN

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor in the liver and the second leading cause of cancer-related death worldwide. The collaborative function between Nucleostemin (NS) and STAT3 has been reported but not well studied in HCC. Here, we found a significant correlation between NS expression and STAT3 phosphorylation, not only in HCC cancers but also in HCC tissues. Patients with high expression of both NS and p-STAT3 show a very poor survival rate. High expression of both NS and p-STAT3 is also associated with tumor size and microvascular invasion. Knocking down the expression of NS greatly reduces the phosphorylation of STAT3. Conversely, overexpression of NS significantly promotes STAT3 phosphorylation. NS and p-STAT3 are located in the nucleus and physiologically interact with each other. Furthermore, NS greatly enhances cell migration and invasion by promoting the epithelial-mesenchymal transition (EMT). NS also supports cell proliferation and colony formation. The importance of NS in HCC was further demonstrated by evaluating tumor formation in vivo. Therefore, we demonstrate a critical collaborative function between NS and STAT3 in HCC, providing an invaluable insight into the mechanism of HCC. The concomitant expression of NS and p-STAT3 might be a potential prognostic indicator and therapeutic target in patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Transición Epitelial-Mesenquimal/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Desnudos , Pronóstico , Transducción de Señal/fisiología
20.
Child Care Health Dev ; 47(6): 869-876, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34265093

RESUMEN

BACKGROUND: Family-centred practice (FCP) has become a recommended practice for early intervention services for children with disabilities in many countries. However, its feasibility in Chinese context has been unclear. This study is the first to explore the perceptions of early intervention service practitioners about the implementation of FCP in mainland China. METHODS: Focus groups were employed to collect data from 37 early intervention practitioners who attended a workshop about FCP in Wuhan, China and two officers from the provincial disabled persons' federation. The data were analysed thematically. RESULTS: Four themes were identified: (a) family-centred early intervention is possible, (b) traditional concepts are not friendly towards FCP, (c) parents do not collaborate and (d) financing and personal resources are not sufficient to implement FCP. Chinese practitioners agreed with the philosophies of FCP; however, there was concern that widespread implementation may meet conceptual and practical challenges. CONCLUSIONS: The results highlighted practitioners were optimistic and keen for FCP implementation in the Chinese context, but to do so across China may still be some way in the future.


Asunto(s)
Niños con Discapacidad , Niño , China , Intervención Educativa Precoz , Estudios de Factibilidad , Humanos , Percepción
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