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1.
Water Res ; 255: 121486, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38564895

RESUMO

This study used a simple mechanical ball milling strategy to significantly improve the ability of Mn2O3 to activate peracetic acid (PAA) for sustainable and efficient degradation of organic micropollutant (like bisphenol A, BPA). BPA was successfully removed and detoxified via PAA activation by the bm-Mn2O3 within 30 min under neutral environment, with the BPA degradation kinetic rate improved by 3.4 times. Satisfactory BPA removal efficiency can still be achieved over a wide pH range, in actual water and after reuse of bm-Mn2O3 for four cycles. The change in hydrophilicity of Mn2O3 after ball milling evidently elevated the affinity of Mn2O3 for binding to PAA, while the reduction in particle size exposed more active sites contributing partially to catalytic oxidation. Further analysis revealed that BPA oxidation in the ball mill-treated Mn2O3 (bm-Mn2O3)/PAA process mainly depends on the bm-Mn2O3-PAA complex (i.e., Mn(III)-OO(O)CCH3) mediated non-radical pathway rather than R-O• and Mn(IV). Especially, the existence of the Mn(III)-PAA complex was definitely verified by in situ Raman spectroscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Simultaneously, density functional theory calculations determined that PAA adsorbs readily on manganese sites thereby favoring the formation of Mn(III)-OO(O)CCH3 complexes. This study advances an in-depth understanding of the underlying mechanisms involved in the manganese oxide-catalyzed activation of PAA for superior non-radical oxidation of micropollutants.

2.
Int J Biol Macromol ; 268(Pt 1): 129220, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38191116

RESUMO

In this work, a total of 18 types of choline chloride, betaine, and L-proline-based deep eutectic solvents (DESs) were synthesized to determine the extraction yield of a natural polysaccharide (PSA) from Dysosma versipellis using an ultrasound-assisted extraction method. Results indicate that the choline-oxalic acid-based DES has the best extraction yield for PSA due to the proper physical-chemical properties between PSA and DES. To evaluate the optimal extraction conditions, a response surface methodology was carried out. Under the optimal conditions, the extraction yield of PSA reaches 10.37 % (± 0.03 %), higher than the conventional extraction methods. Findings from FT-IR and NMR suggest that the extracted PSA belongs to a neutral polysaccharide with (1 â†’ 6)-linked α-d-glucopyranose in the main chain. Interestingly, results from various electrochemical measurements show the extracted PSA exhibits excellent corrosion inhibition performance for mild steel (MS) in a 0.5 M HCl solution, with 90.8 % of maximum corrosion inhibition efficiency at 210 mg L-1. SEM and XPS measurements reveal the formation of a protective layer on the MS surface. The adsorption behaviour of extracted PSA well obeys the Langmuir adsorption isotherm containing the chemisorption and physisorption. Additionally, theoretical calculations validate the experimental findings.


Assuntos
Solventes Eutéticos Profundos , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Corrosão , Solventes Eutéticos Profundos/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Aço/química
3.
Int J Biol Macromol ; 242(Pt 2): 124712, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148938

RESUMO

In this work, Glucomannan was modified with dopamine to synthesize a new polysaccharide Schiff base (GAD). After confirmation of GAD by NMR and FT-IR spectroscopic methods, it was introduced as a sustainable corrosion inhibitor with excellent anti-corrosion action for mild steel in 0.5 M hydrochloric acid (HCl) solution. Employing electrochemical test, morphology measurement, and theoretical analysis, the anticorrosion performance of GAD on mild steel in 0.5 M HCl solution is determined. Maximum efficiency of GAD for suppressing the corrosion rate of mild steel at 0.12 g L-1 reaches 99.0 %. After immersion in HCl solution for 24 h, the results from scanning electron microscopy indicate that GAD is firmly attached to the mild steel surface by making a protective layer. According to the X-ray photoelectron spectroscopy (XPS), FeN bonds existed on the steel surface indicate the presence of chemisorption between GAD and Fe to form stable complexes attracted to the active position on the mild steel. The effects of Schiff base groups on the corrosion inhibition efficiencies were also investigated. Moreover, the inhibition mechanism of GAD was further illustrated by the free Gibbs energy, quantum chemical calculation and molecular dynamics simulation.


Assuntos
Dopamina , Ácido Clorídrico , Ácido Clorídrico/química , Espectroscopia de Infravermelho com Transformada de Fourier , Aço/química , Bases de Schiff , Ácidos
4.
J Hazard Mater ; 452: 131286, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37001209

RESUMO

As a novel strategy, peracetic acid (PAA) based advanced oxidation processes (AOPs) are being used in micropollutant elimination due to their high oxidation and low toxicity. In this study, Co2Ca1Al1-LDO as a kind of layered double oxides (LDOs) was successfully synthesized, and it is the first time to apply Co2Ca1Al1-LDO for activating PAA. The Co2Ca1Al1-LDO/PAA system showed excellent removal efficiencies for various micropollutants with removal ratios ranging from 90.4% to 100% and k values from 0.087 min-1 to 0.298 min-1. In the degradation period, various reactive oxygen species (ROS) are involved in the system, while organic radicals (R-O•) with a high concentration of 5.52 × 10-13 M are the dominant ROS in the contaminants degradation process. Compared to other ROS, R-O• had the largest contribution ratio (more than 85%) to pollutant degradation. Further analysis demonstrated that C1, C2, C3, C4, C5, C6 and N11 concentrated on the aniline group of SMX are the main attack sites based on the density functional theory (DFT) results, which is consistent with the degradation products. The toxicity of contaminants was obviously reduced after removing in this system. Furthermore, Co2Ca1Al1-LDO showed good reusability and stability, and Co2Ca1Al1-LDO/PAA system had excellent removal ability in actual water bodies containing inorganic anions, showing good application potential. Importantly, this study explored the feasibility of applying LDO catalysts in PAA-based AOPs for micropollutants elimination, providing new insights for subsequent research.

5.
Water Res ; 232: 119666, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36731206

RESUMO

As an oxidant, peracetic acid (PAA) is gradually applied in advanced oxidation processes (AOPs) for pollutants degradation due to its high oxidation and low toxicity. In this study, the prepared Co2Fe1-LDH showed excellent PAA activation ability for efficient degradation of various pharmaceuticals with a removal efficiency ranging from 82.3% to 100%. Taking sulfamethoxazole (SMX) as a model pharmaceutical, it's found that organic radical (R-O•) with high concentration of 5.27 × 10-13 M is the dominant ROS responsible for contaminants degradation. Further analysis demonstrated that bimetallic synergistic effect between Co and Fe can improve electron transfer ability of Co2Fe1-LDH, resulting in the accelerated conversion of Co from +3 to +2 valence state with a high reaction rate (4.3 × 101-1.483 × 102 M-1 s-1) in this system. Density functional theory (DFT) reveals that C1, C3, C5 and N11 with higher ƒ0 and ƒ-values concentrated on aniline group of SMX are the main attack sites, which is consistent with the results of degradation products. Besides, Co2Fe1-LDH/PAA system can effectively reduce biological toxicity after reaction, due to lower biotoxicity of degradation products and the carbon sources provided by PAA. In application, Co2Fe1-LDH/PAA system was capable of resisting the influence of water matrix and effectively removing pollutants in actual hospital wastewater. Importantly, this study comprehensively evaluated the ability of Co2Fe1-LDH/PAA system to remove organics and improve the biodegradability of actual hospital wastewater, providing guidance for application of PAA activation system.


Assuntos
Ácido Peracético , Poluentes Químicos da Água , Águas Residuárias , Peróxido de Hidrogênio , Sulfametoxazol , Oxirredução , Preparações Farmacêuticas
6.
Water Res ; 222: 118887, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35907302

RESUMO

In this study, mechanically sulfidated microscale zero valent iron (S-ZVI) was found to effectively activate the peracetic acid (PAA) with a result of almost complete degradation of six micropollutants within 10 min under neutral conditions, and > 95% sulfamethoxazole (SMX) removal after six cycles. Reactive oxidized species (ROS) including HO•, carbon-centered radicals, and Fe(IV) were generated in the S-ZVI/PAA system, while HO• was the main contributor towards micropollutants degradation. This study clearly revealed that enhancement of the electron donating ability of ZVI by the formed conductive iron sulfides was crucial for promoted Fe(II) generation and subsequent PAA activation over several cycles, rather than the ability of sulfides to reduce Fe(III) for Fe(II) regeneration as reported previously. Interestingly, it's discovered that co-existence of Fe(III) would dramatically improve the contaminants removal efficiency of the S-ZVI/PAA system; transform the surfaced Fe(II) dominated ROS generation process to aqueous Fe(II) one; enhance the tolerance of the proposed system to water matrix. The promoting effect of predosed Fe(III) on PAA activation by S-ZVI should be mainly associated with: the greater ability of Fe(III) than H2O to accept electron from Fe0 for obtaining more active sites; slower Fe0 consumption and solid sulfur species release for elevated electron utilization efficiency and PAA activation. Considering the convenient and cost-effective access of Fe(III), the decrease of acute toxicity of treated SMX, excellent stability and good removal of various micropollutants fully demonstrate the superiority of S-ZVI/PAA system for practical application.


Assuntos
Ferro , Poluentes Químicos da Água , Compostos Ferrosos , Ferro/química , Ácido Peracético , Espécies Reativas de Oxigênio , Sulfametoxazol , Sulfetos
7.
Environ Sci Technol ; 56(12): 8784-8795, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35584301

RESUMO

In this study, the previously overlooked effects of contaminants' molecular structure on their degradation efficiencies and dominant reactive oxygen species (ROS) in advanced oxidation processes (AOPs) are investigated with a peroxymonosulfate (PMS) activation system selected as the typical AOP system. Averagely, degradation efficiencies of 19 contaminants are discrepant in the CoCaAl-LDO/PMS system with production of SO4•-, •OH, and 1O2. Density functional theory calculations indicated that compounds with high EHOMO, low-energy gap (ΔE = ELUMO - EHOMO), and low vertical ionization potential are more vulnerable to be attacked. Further analysis disclosed that the dominant ROS was the same one when treating similar types of contaminants, namely SO4•-, 1O2, 1O2, and •OH for the degradation of CBZ-like compounds, SAs, bisphenol, and triazine compounds, respectively. This phenomenon may be caused by the contaminants' structures especially the commonly shared or basic parent structures which can affect their effective reaction time and second-order rate constants with ROS, thus influencing the contribution of each ROS during its degradation. Overall, the new insights gained in this study provide a basis for designing more effective AOPs to improve their practical application in wastewater treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Estrutura Molecular , Oxirredução , Peróxidos/química , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/química
8.
Transpl Immunol ; 73: 101603, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35452830

RESUMO

OBJECTIVE: Severe acute pancreatitis (SAP) is a highly morbid condition in general population as well as in solid organ transplant (SOT) recipients. The present study aimed to investigate the effect of continuous renal replacement therapy (CRRT) with different anticoagulation methods on the expression levels of cytokines in SAP. METHODS: A total of 120 patients with SAP, admitted into our hospital between September 2017 and July 2020, were enrolled as the research subjects and randomly divided into a control group (60 cases) and a study group (60 cases). CRRT with low molecular weight (LMW) heparin­calcium anticoagulation was conducted on patients in the control group, and CRRT with topical citrate + low-dose LMW heparin­calcium anticoagulation was conducted on patients in the study group. The expressions of cytokines in the two groups were compared after treatment. RESULTS: There was no significant difference in white blood cells (WBC), C-reactive proteins (CRP), and procalcitonin (PCT) before treatment between the two groups (P > 0.05). After treatment, the levels of WBC (P = 0.006), CRP (P < 0.001), and PCT (P < 0.001) were significantly lower in the study group when compared with those in the control group. There was no significant difference in the concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) between the two groups before treatment (P > 0.05). After treatment, the concentrations of IL-6, IL-8, and TNF-α were significantly lower in the study group when compared with those in the control group. The APACHEII, SOFA and Ranson scores of the two groups were analyzed, and there was no difference between the two groups before treatment (P > 0.05). After treatment, the score of the study group was lower than that of the control group (P < 0.05). CONCLUSION: CRRT with topical citrate + low-dose LMW heparin­calcium anticoagulation in the treatment of patients with SAP reduces the levels of WBC, CRP, and PCT and the concentrations of cytokines, including IL-6, IL-8, and TNF-α. This inhibits the release of inflammatory mediators in patients with SAP and reduces damage to the body caused by the inflammatory response, thus effectively improving the patients' condition.


Assuntos
Terapia de Substituição Renal Contínua , Pancreatite , Doença Aguda , Anticoagulantes/uso terapêutico , Proteína C-Reativa , Citratos , Citocinas , Humanos , Interleucina-6 , Interleucina-8 , Pancreatite/tratamento farmacológico , Terapia de Substituição Renal/métodos , Fator de Necrose Tumoral alfa
9.
Water Res ; 217: 118402, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35417819

RESUMO

As peracetic acid (PAA) is being increasingly used as an alternative disinfectant, efficient activation of PAA by low-cost and environmentally friendly catalysts over a wide pH range is potentially useful for simultaneous sterilization and pharmaceutical degradation in wastewater, such as hospital wastewater. In this study, peracetic acid (PAA) was successfully activated by low-cost and environmental-friendly FeS (25 mg/L) for efficient oxidative removal of three pharmaceuticals over a wide pH range (3.0∼9.0) as indicated by 80∼100% removal rate within 5 min. As expected, Fe(II) rather than sulfur species was the primary reactive site for PAA activation, while unlike the homogeneous Fe2+/PAA system with organic radicals (R-O·) and ·OH as the dominant reactive oxidized species (ROS), ·OH is the key reactive species in the FeS/PAA system. Interestingly and surprisingly, in-depth investigation revealed the dual role of sulfur species in regulating the reactive oxidized species: (1) S(-II) and its conversion product H2S (aq) played a significant role in Fe(II) regeneration with a result of accelerated PAA activation; (2) however, the R-O· generated in the initial seconds of the FeS/PAA process was supposed to be quickly consumed by sulfur species, resulting in ·OH as the dominant ROS over the whole process. The selective reaction of sulfur species with R-O· instead of ·OH was supported by the obviously lower Gibbs free energy of CH3COO· and sulfur species than ·OH, suggesting the preference of CH3COO· to react with sulfur species with electron transfer. After treatment with the FeS/PAA system, the products obtained from the three pharmaceuticals were detoxified and even facilitated the growth of E. coli probably due to the supply of numerous carbon sources by activated PAA. This study significantly advances the understanding of the reaction between PAA and sulfur-containing catalysts and suggests the practical application potential of the FeS/PAA process combined with biotreatment processes.


Assuntos
Ácido Peracético , Poluentes Químicos da Água , Escherichia coli , Compostos Ferrosos , Peróxido de Hidrogênio , Oxirredução , Preparações Farmacêuticas , Espécies Reativas de Oxigênio , Enxofre , Águas Residuárias , Poluentes Químicos da Água/análise
10.
Biochem Biophys Res Commun ; 522(1): 53-60, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31735331

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide. Protein tyrosine phosphatase 1B (PTP1B) is a member of protein tyrosine phosphatases (PTPs) family. In our previous work, PTP1B was found to be overexpressed in ESCC tissues and made contributions to the the cell migration and invasion as well as lung metastasis of ESCC. In this study, we explored the underlying molecular mechanisms. PTP1B enhanced cell migration and invasion by promoting epidermal growth factor receptor (EGFR) expression in ESCC, which was relied on phosphatase activity of PTP1B. Using GST-pulldown combined with LC/MS/MS, we found that nonmuscle myosin IIA (MYH9) was a novel substrate of PTP1B in ESCC cells. PTP1B dephosphorylated MYH9 at Y1408, by which PTP1B up-regulated EGFR expression and enhanced cell migration and invasion in ESCC. In conclusion, our study first reported that PTP1B was the positive regulator of EGFR by dephosphorylating MYH9 at Y1408 to promote cell migration and invasion, which revealed the regulatory mechanism of PTP1B-MYH9-EGFR axis in ESCC.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Cadeias Pesadas de Miosina/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Receptores ErbB/metabolismo , Humanos , Invasividade Neoplásica , Fosforilação , Regulação para Cima
11.
Nanomaterials (Basel) ; 8(6)2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880770

RESUMO

NiAl-layered double hydroxide (NiAl-LDH) coatings grown in-situ on AZ31 Mg alloy were prepared for the first time utilizing a facile hydrothermal method. The surface morphologies, structures, and compositions of the NiAl-LDH coatings were characterized by scanning electron microscopy (SEM), three dimensional (3D) optical profilometer, X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR), and X-ray photoelectron spectroscopy (XPS). The results show that NiAl-LDH coating could be successfully deposited on Mg alloy substrate using different nickel salts, i.e., carbonate, nitrate, and sulfate salts. Different coatings exhibit different surface morphologies, but all of which exhibit remarkable enhancement in corrosion protection in 3.5 wt % NaCl corrosive electrolyte. When nickel nitrate was employed especially, an extremely large impedance modulus at a low frequency of 0.1 Hz (|Z|f= 0.1 Hz), 11.6 MΩ cm², and a significant low corrosion current density (jcorr) down to 1.06 nA cm-2 are achieved, demonstrating NiAl-LDH coating's great potential application in harsh reaction conditions, particularly in a marine environment. The best corrosion inhibition of NiAl-LDH/CT coating deposited by carbonate may partially ascribed to the uniform and vertical orientation of the nanosheets in the coating.

12.
Micron ; 112: 69-83, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29929172

RESUMO

One of the biggest challenges in corrosion investigation is foreseeing precisely how and where materials will degenerate in a designated condition owing to scarceness of accurate corrosion mechanisms. Recent fast development of in situ transmission electron microscopy (TEM) technique makes it achievable to better understand the corrosion mechanism and physicochemical processes at the interfaces between samples and gases or electrolytes by dynamical capture the microstructural and chemical changes with high resolution within a realistic or near-realistic environment. However, a detailed and in-depth account summing up the development and latest achievements of in situ TEM techniques, especially the application of emerging liquid and electrochemical cells in the community of corrosion study in the last several years is lacking and is urgently needed for its heathy development. To fill this gap, this critical review summarizes firstly the key scientific issues in corrosion research, followed by introducing the configurations of several typical closed-type cells. Then, the achievements of in situ TEM using open-type or closed-type cells in corrosion study are presented in detail. The study directions in the future are commented finally in terms of spatial and temporal resolution, electron radiation, and linkage between microstructure and electrochemical performance in corrosion community.

13.
Oncogene ; 37(24): 3260-3274, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29551772

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the malignancies in digestive system, with a low 5-year survival rate. We previously revealed that Sequestosome 1 (SQSTM1/p62) protein levels were upregulated in ESCC tissues. However, it is unclear about the function of p62 and the underlying mechanism. Here, we used immunofluorescence and immunohistochemistry to investigate the expression of p62 in ESCC. Western blotting, quantitative RT-PCR, colony formation assay, flow cytometry, immunoprecipitation and xenograft tumor assay were used to analyze the role of p62 in vitro and vivo. Here, we showed that p62 serves as a regulator of cell apoptosis under serum starvation condition in ESCC cells. Through activating the protein kinase C iota (PKCiota)-S-phase kinase-associated protein 2 (SKP2) signaling pathway, p62 enhances cell apoptosis resistance and colony formation in vitro and tumor growth in mouse models. Through interaction with the domains PB1, p62 upregulated the expression of PKCiota and then depressed the ubiquitin-mediated proteasomal degradation of SKP2. p62-silencing combined with a PKCiota inhibitor ATM significantly enhanced cell apoptosis and inhibited cell survival. Immunohistochemical analysis revealed a positive association between the expression of p62 and SKP2 in primary ESCC tissues. And importantly, p62 presented a markedly cytoplasmic translocation in cancerous cells, including in 16 (30.76%) tumors at stage T1, as compared with its nuclear location in normal esophageal epithelial cells. In summary, p62 plays an anti-apoptotic role in ESCC cells via stabilizing SKP2 under serum starvation condition. These data suggest that p62 might be an early biomarker and a candidate therapeutic target of ESCC.


Assuntos
Apoptose/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Proteína Sequestossoma-1/genética , Animais , Linhagem Celular Tumoral , Meios de Cultura , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Camundongos Endogâmicos BALB C , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Estabilidade Proteica , Proteínas Quinases Associadas a Fase S/genética , Proteína Sequestossoma-1/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Chin Med J (Engl) ; 131(3): 323-329, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29363648

RESUMO

BACKGROUND: Snakebites are a neglected threat to global human health with a high morbidity rate. The present study explored the efficacy of antivenom with hyperbaric oxygen (HBO) intervention on snakebites, which could provide the experimental basis for clinical adjuvant therapy. METHODS: Male Sprague-Dawley rats (n = 96) were randomized into four groups: the poison model was established by injecting Deinagkistrodon acutus (D. acutus) venom (0.8 LD50) via the caudal vein; the antivenom group was injected immediately with specific antivenom via the caudal vein after successful establishment of the envenomation model; and the antivenom + HBO group was exposed to HBO environment for 1 h once at predetermined periods of 0 h, 4 h, 12 h, and 23 h after antivenin administration. Each HBO time point had six rats; the control group was left untreated. The rats in the experimental group were euthanized at the corresponding time points after HBO therapy, and brain tissue and blood were harvested immediately. Hematoxylin and eosin (H&E) staining was used to investigate the pathological changes in the rat brain. Immunohistochemistry (IHC), real-time polymerase chain reaction (PCR), and Western blotting were used to detect the expression of Nestin mRNA and protein in the subventricular zone (SVZ) of the brain. The levels of coagulation function (prothrombin time, activated partial thromboplastin time [APTT], and fibrinogen) and oxidation/antioxidation index (malondialdehyde [MDA] and superoxide dismutase [SOD]) were analyzed. Data were analyzed using one-way analysis of variance. RESULTS: The brain tissue from rats in the poison model was observed for pathological changes using H&E staining. Tissues showed edema, decreased cell number, and disordered arrangement in the SVZ in the snake venom group. The antivenom - HBO intervention significantly alleviated these observations and was more prominent in the antivenom + HBO group. The serum levels of SOD and MDA in the snake venom group were increased and the antivenom - HBO intervention further increased the SOD levels but significantly decreased the MDA levels; however, this was enhanced within 1 h after HBO administration (MDA: F = 5.540, P = 0.008, SOD: F = 7.361, P = 0.000). Activated partial thromboplastin time (APTT) was significantly abnormal after venom administration but improved after antivenom and was even more significant in the antivenom + HBO group 5 h after envenomation (F = 25.430, P = 0.000). Only a few nestin-positive cells were observed in the envenomation model. The expression levels were significant in the antivenom and antivenom + HBO groups within 1 and 5 h after envenomation and were more significant in the antivenom + HBO group as determined by IHC, real-time PCR, and Western blotting (P < 0.05). D. acutus envenomation has neurotoxic effects in the brain of rats. CONCLUSIONS: Antivenin and HBO, respectively, induced a neuroprotective effect after D. acutus envenomation by attenuating brain edema, upregulating nestin expression in SVZ, and improving coagulopathy and oxidative stress. The intervention efficacy of antivenom with HBO was maximum within 5 h after envenomation and was more efficacious than antivenom alone.


Assuntos
Antivenenos/uso terapêutico , Mordeduras de Serpentes/terapia , Animais , Antioxidantes/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Venenos de Crotalídeos , Expressão Gênica , Oxigenoterapia Hiperbárica , Masculino , Malondialdeído/metabolismo , Nestina/genética , Nestina/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Mordeduras de Serpentes/patologia , Venenos de Serpentes , Superóxido Dismutase/metabolismo
15.
ACS Appl Mater Interfaces ; 9(41): 36247-36260, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28945337

RESUMO

The ability to manipulate the functionalization of Ni coating is of great importance in improving the corrosion resistance of magnesium (Mg) alloy for many industrial applications. In the present work, MCM-41 type mesoporous silica nanocontainers (MSNs) loaded with corrosion inhibitor (NaF) were synthesized and employed as smart reinforcements to enhance the integrity and corrosion inhibition of the Ni coating. The incorporation of the F-loaded MSNs (F@MSNs) to enhance the corrosion resistant capacity of a metallic coating is reported for the first time. The mesoporous structures of the as-prepared MSNs and F@MSNs were confirmed by transmission electron microscopy (TEM), small angle X-rays scattering (SAXS), and N2 adsorption-desorption isotherms. The X-ray photoelectron spectroscopy (XPS) data demonstrated the successful immobilization of fluoride ion on the MSNs and formation of a magnesium fluoride (MgF2) protective film at the corrosion sites of the Mg alloy upon soaking in a F@MSNs-containing NaCl solution. The results from potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) for both bare Mg alloy and Ni coatings with and without F@MSNs have revealed a clear decrease in corrosion rate in a corrosive solution for a long-time immersion due to the introduction of F@MSNs. These findings open new opportunities in the exploration of self-healing metallic coatings for highly enhanced anticorrosion protection of Mg alloy.

16.
Onco Targets Ther ; 10: 3743-3754, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28794639

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a highly malignant tumor associated with a poor prognosis, and the molecular mechanisms underlying its formation and progression remain poorly understood. KIAA1522 is upregulated in various tumor tissues, but its function is unknown. Alterations in KIAA1522 expression and its implication in ESCC are currently unclear. In this study, an immunohistochemical analysis of ESCC tissues showed that KIAA1522 was highly expressed in 46% (157/342) of ESCC specimens and that its expression was inversely correlated with the degree of differentiation (P=0.03). Furthermore, small interfering RNA-mediated silencing of KIAA1522 revealed that overexpression of this protein reinforced malignant cell proliferation and anoikis resistance of ESCC cells in vitro. More importantly, KIAA1522 depletion significantly suppressed the growth of ESCC xenograft tumors and lung metastasis of ESCC cells in nude mice. At the molecular level, inhibition of KIAA1522 expression markedly reduced the phosphorylated extracellular signal-regulated kinase (ERK) levels in both suspended and adherent ESCC cells, suggesting that KIAA1522 might promote cell proliferation and survival via the ERK cascade. Taken together, these data suggest that upregulation of KIAA1522 might enhance tumorigenicity and metastasis of ESCC cells through potentiating the ERK activity. Thus, aberrant expression of KIAA1522 plays oncogenic roles in ESCC and might serve as a novel molecular target in ESCC treatment.

17.
J Xray Sci Technol ; 25(6): 981-991, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28697579

RESUMO

PURPOSE: To explore the value of low-dose CT perfusion imaging (LDCTPI) technology and its perfusion parameters in assessing response of neoadjuvant chemotherapy (NAC) in patients with advanced gastric cancer (AGC). METHODS: Thirty patients with AGC were studied prospectively by LDCTPI to measure two parameters including blood flow (BF) and blood volume (BV) of tumor area before and after chemotherapy, respectively. All of the patients received two courses of NAC and surgical resection of gastric tumor within one week after chemotherapy, and then obtained the result of postoperative pathology response for chemotherapy. The comparisons of BF and BV values of AGC before and after chemotherapy were analyzed by paired-samples t-test, respectively; and the correlations between BF as well as BV decrease rates after NAC and the pathology response grade were analyzed by Spearman statistical test. Thirty patients were divided into effective and ineffective groups according to different pathology response grade. Comparisons of BF as well as BV decrease rates between effective and ineffective groups were analyzed by independent-samples t-test, respectively. Receiver operating characteristic (ROC) curves were used to determine the cutoff values of BF and BV decrease rates as evaluation indicators of AGC after NAC and calculate area under the curve (AUC). RESULTS: There were significant differences in BF and BV values of AGC between before and after NAC (p < 0.001), respectively, and there were obvious correlations between BF as well as BV decrease rates and pathology response grade (r = 0.660, p < 0.001; r = 0.706, p < 0.001), respectively. There were also significant differences in BF and BV decrease rates of AGC between effective and ineffective groups (P = 0.001), respectively. If BF decrease rate of 12.1% (AUC was 0.816, P = 0.005) was used as the cutoff value for chemotherapy effectiveness of AGC, the sensitivity of 82% and specificity of 84% were achieved, and if BV decrease rate of 32.8% (AUC was 0.844, P = 0.002) was used as the cutoff value for chemotherapy effectiveness of AGC, the sensitivity of 82% and specificity of 89% were achieved. CONCLUSIONS: BF and BV decrease rates have potential to be used as effective indicators to assess chemotherapy efficacy of AGC from the hemodynamics.


Assuntos
Terapia Neoadjuvante/métodos , Doses de Radiação , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/tratamento farmacológico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estômago/diagnóstico por imagem
18.
J Xray Sci Technol ; 25(5): 847-855, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28598862

RESUMO

PURPOSE: To investigate feasibility of applying low-dose CT perfusion imaging (CTPI) to diagnose gastric cancer. MATERIALS AND METHODS: Twenty patients with gastric cancer confirmed by endoscopic biopsy were undergone routine dose (120 kV, 100 mA) and low-dose (120 kV, 50 mA) CTPI examination, respectively. The original data were processed by body perfusion software, and the perfusion parameters values including blood flow (BF), blood volume (BV) and permeability surface (PS) of gastric cancer were measured. Statistical data analyses including paired-samples t test, Pearson correlation analysis and Bland-Altman consistency test were used to compare the perfusion parameters values between the routine dose and low-dose CTPI examinations. Radiation dosage, which the patients received during two CTPI examinations, was also calculated and compared. RESULTS: There were no statistical differences in the BF, BV and PS values between routine dose group and low-dose group (P > 0.05), and there were significant correlation in the BF, BV and PS values between two groups (P <  0.01). The consistency of BF and BV values between the two groups was preferable to that of PS value. The radiation dosage of the low-dose group was much less than that of routine dose group, and the CTDIvol and DLP values of low-dose CTPI were decreased by 50%, respectively. CONCLUSION: The parameters BF and BV values may play a valuable role in the diagnosis and assessment of gastric cancer in low-dose CTPI examination.


Assuntos
Imagem de Perfusão/métodos , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Ann Transplant ; 22: 75-82, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28184034

RESUMO

BACKGROUND Ischemia-reperfusion injury (IRI) is a clinically common pathologic process defined as the inability to improve neuronal function. This study aimed to investigate the pathological mechanism of IRI and to explore effects of hyperbaric oxygenation (HBO) on autophagy and inflammatory response in IRI. MATERIAL AND METHODS Ninety Sprague-Dawley (SD) rats were randomly divided into a Sham group, a kidney transplant group (Trans), and a kidney transplant plus HBO treatment group (Trans+HBO). The kidney was harvested from the donor and transplanted to recipient rats according to a previously reported study. Rats were anesthetized using pentobarbital-natrium, and the kidney was resected and fixed in 4% paraformaldehyde. Serum creatinine (Scr) was detected using an automatic biochemical analyzer. The interleukin-6 (IL-6) level was assessed using enzyme-linked immunosorbent assay (ELISA). LC-3 was examined using indirect immunofluorescence assay and immunochemistry assay. LC-3 mRNA levels were analyzed using real-time PCR (RT-PCR). RESULTS The kidney transplant IRI model was successfully established. Scr and IL-6 levels were significantly increased in the Trans group (P<0.05). HBO significantly enhanced Scr and IL-6 levels. Scr was positively correlated with IL-6 levels (r-0.607, P<0.05). HBO increased LC-3 protein and mRNA expression in kidney-transplanted rats compared to the Sham and Trans group (P<0.05). Moreover, immunofluorescence assay also showed that LC-3 protein mainly distributes along renal tubular epithelial cells in a linear manner. CONCLUSIONS Autophagy dysfunction and inflammatory response after renal transplantation play important roles in processes of IRI. HBO treatment protects against the renal injury of IRI in renal tissues at the early stage, which may be triggered by the IL-6 pathway.


Assuntos
Autofagia/fisiologia , Oxigenoterapia Hiperbárica , Inflamação/patologia , Rim/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Animais , Creatinina/sangue , Inflamação/sangue , Interleucina-6/sangue , Rim/patologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/patologia
20.
J Cancer Res Clin Oncol ; 142(6): 1285-97, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26864695

RESUMO

PURPOSE: The Glasgow Prognostic Score (GPS) and modified Glasgow Prognostic Score (mGPS) are shown to be reliable prognostic indexes in patients with operable and inoperable non-small cell lung cancer (NSCLC). Considering the difference between the two indexes lies in whether hypoalbuminemia without an elevated C-reactive protein (CRP) is associated with worse survival, this study aims to evaluate the prognostic performance of hypoalbuminemia in patients without an elevated CRP and to compare the prognostic value of GPS and mGPS in patients with operable and inoperable NSCLC. METHODS: The data of 2988 patients were retrospectively collected from the Shanghai Health Information Network. Univariate and multivariate Cox regression was performed to investigate the prognostic effect of albumin, CRP, GPS and mGPS. Restricted cubic spline was also performed to evaluate the relationship between albumin and hazard ratio. Kaplan-Meier survival curves were estimated and compared using the log-rank test. Additional discriminative ability of GPS and of mGPS was evaluated using the area under the curve and Harrell's concordance index. RESULTS: Hypoalbuminemia was associated with worse survival in both operable and inoperable patients without an elevated CRP. The Kaplan-Meier survival curve of hypoalbuminemic patients without an elevated CRP was more close to the curve of patients with an elevated CRP and a normal albumin than to the curve of patients with neither of these abnormalities. Multivariate analysis, AUC and C-index all indicated that GPS had a higher prognostic value than mGPS. CONCLUSIONS: Hypoalbuminemia was associated with worse survival in patients with or without an elevated CRP. GPS was superior to mGPS in predicting survival in operable and inoperable NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Idoso , Proteína C-Reativa/metabolismo , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Albumina Sérica/metabolismo
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