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1.
J Colloid Interface Sci ; 672: 415-422, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850866

RESUMO

To achieve rapid preparation of hydrogels without using conventional chemical initiators, a stable suspension of eutectic gallium indium (EGaIn) liquid metal nanoparticles is explored by probe-sonicating the metal in an aqueous solution. Liquid metal suspension was sonicated to serve as a photo-initiator for acrylamide polymerization and produce hydrogels. The initiation effect comes from the fact that liquid metal suspension after sonication can produce a large number of free radicals when exposed to ultraviolet (UV) radiation, leading to initiation. The changes of liquid metal nanodroplets under UV light irradiation have been systematically investigated. Further, the liquid metal colloidal solutions were used to prepare hydrogels with the same transparency and adjustable mechanical properties as the samples initiated by commercial photo-initiators. This work shows the great application potential of liquid metal in the preparation of hydrogels and provides a new technical idea for the design of multifunctional hydrogels.

2.
J Colloid Interface Sci ; 638: 313-323, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746050

RESUMO

Carbon nanotubes (CNTs) usually served as conductive and reinforcing nanofillers for making nanocomposites have never been reported to play a role in accelerating fabrication of hydrogels. Herein, we report an important discovery that by involving CNTs and liquid metal (LM) to form a complex (LM@CNTs), multifunctional hydrogels are rapidly prepared from vinyl monomers without heating or adding any initiators and crosslinkers. Study results demonstrate that LM@CNTs not only performs as both initiator and crosslinker for synthesizing hydrogels, but also dramatically reduces the polymerization duration from 3 days to minute levels, compared with that of only LM involved in hydrogel fabrication. Specifically, the complex initiates (<60 s) and crosslinks (<8min) monomers to form the high-performance hydrogels, which significantly reduces energy consumptions. The resulting polyacrylic acid (PAA) hydrogel possesses super stretchability (∼1200 %), high tensile strength (0.96 MPa), outstanding strain sensitivity (Gauge factor = 15.40 at 300-500 % strain), and excellent adhesion to various substrate surfaces. Additionally, the injectable molding performance will benefit the mass production of the hydrogels, which exhibits great potential for applications of wearable flexible sensors. This study provides an environmentally friendly, rapid polymerization, and energy-saving strategy by effectively applying nano-fillers for viable fabrication and application of multifunctional hydrogels.

3.
J Colloid Interface Sci ; 638: 392-402, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36758252

RESUMO

Carbon nanofiber (CNF)/polycaprolactone (PCL) composites were three-dimention (3D) printed into electromagnetic interference (EMI) shielding parts. 3D-printing process led to an inhomogeneous CNFs distribution in printed composites. The special high-resistance "internal surfaces" introduced between printed threads reduced the conductivity of printed parts and resulted in characteristic secondary percolation phenomena. Meanwhile, the accelerated melt flow in nozzle oriented CNFs in composites along the printing direction, increasing the percolation threshold compared to the random arrangement. As two stage of percolation networks formed, the 3D-printed CNF/PCL parts exhibited excellent EMI shielding performance, with EMI shielding effectiveness value up to 58.7 dB. By controlling the packing density of the printed part, a large number of apertures and heterogeneous interfaces were easily introduced into the interior of parts. It promoted multiple reflection and absorption of electromagnetic waves inside the parts, and enabled adjustment of weight and shielding effectiveness. Therefore, the 3D printing enabled the flexible formation of complex porous structures. From basic materials to designed components, the 3D printing technology can facilitate the transformation of shielding materials into high performance components that are finely designed both internally and externally, making it a promising technology in the field of manufacturing lightweight, high performance EMI shielding materials.

4.
Small Methods ; 6(12): e2201114, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36336652

RESUMO

Safety of lithium metal batteries (LMBs) has been improved by using the solid-state polymer electrolytes, but the performance of LMBs is still troubled by the poor interface of solid electrolytes/electrodes, leading to insufficient interfacial Li+ transport. Here, a novel ultrathin, robust-flexible polymeric electrolyte is achieved by in situ polymerization of 1,3-dioxolane in soft nanofibrous skeleton at room temperature without any extra initiator or plasticizer, leading to the electrolyte with rapid interfacial ion transport. This facilitated Li+ transportation is demonstrated by molecular dynamics simulation. Consequently, the as-prepared electrolyte exhibits excellent cycling performance. The results indicate that the electrolyte works well in the LiFePO4 //Li cell at elevated temperature up to 90 °C, and further matches with the high-voltage LiNi0.8 Mn0.1 Co0.1 O2 cathode. This study provides an effective approach to constructing a practical polymeric electrolyte for fabrication of safe, high performance LMBs.

5.
J Colloid Interface Sci ; 627: 90-101, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35842969

RESUMO

Metal-organic framework materials (MOF) have become a new generation of microwave absorption (MA) materials. However, it is still challenging to design an appropriate microstructure that can efficiently adjust the microwave absorbing characteristics. Herein, a novel bimetal-doped core-shell carbon derived from nickel-cobalt dual-ligand MOF has been successfully prepared. By changing the ratio of the second ligand, the morphology can change from sea urchin-like to rod-like and petal-like shapes, thereby regulating the final wave absorption performance of MOF derivatives. The Bi-MOF-1 exhibited strong microwave absorption (up to -70.70 dB), while Bi-MOF-2 presented broad effective absorption bandwidth (5.92 GHz). The analyses indicated that the excellent impedance matching can be attributed to the double-layer magnetic loss and multiple dielectric loss of the core-shell structure. This work provides a feasible approach for the design and preparation of functional composite structures based on MOF derivatives with controllable microwave absorbing properties.

6.
J Phys Chem B ; 126(24): 4531-4542, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35695471

RESUMO

The association of ions describes the formation of ion species in electrolyte solutions and is strongly related to the salt concentration. However, the discussion of ion species and their transport is ambiguous in some studies on electrolyte materials due to the assumption of ideal solutions. Accordingly, in this work, molecular dynamics simulations are used to study ion association and transport properties of poly(ethylene)oxide (PEO)-lithium bis(trifluoromethanesulfonyl)imide electrolytes over a range of salt concentrations (r = [Li]/[EO]) from 0.01 to 0.20. Based on the analysis of the solvation environment and ion species, it is revealed that the distinct ion-ion correlations exist in two different characteristic areas, with a salt concentration of 0.10 as the limit. Below the critical concentration, the dynamic equilibrium between free ions and ion pairs is the most important process affecting the transport properties of electrolytes, but the process may have a minor influence on the applicability of the Nernst-Einstein relation. In concentrated solutions, a large number of ion pairs, triplets, and so forth appear in the electrolytes. The high-order ion clusters, with an average size of 3.95 at r = 0.20, are the main stable structures for transporting Li+, but the trapped free ions are the most abundant ion species. Meanwhile, the effect of salt concentrations on the average transport of ion clusters is to increase their average lifetime, but their transport rates remain unchanged. In addition, the coupling dynamics between ions and polymers is also discussed in order to gain a complete insight into the importance of salt concentrations.

7.
Adv Sci (Weinh) ; 9(4): e2103663, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34894106

RESUMO

Lithium metal battery (LMB) possessing a high theoretical capacity is a promising candidate of advanced energy storage devices. However, its safety and stability are challenged by lithium dendrites and the leakage of liquid electrolyte. Here, a self-enhancing gel polymer electrolyte (GPE) is created by in situ polymerizing 1,3-dioxolane (DOL) in the nanofibrous skeleton for enabling safe LMB. The nanofiber membrane possesses a better affinity with poly-DOL (PDOL) than commercial separator for constructing homogeneous GPE with enhanced ion conductivity. Furthermore, polydopamine is introduced on nanofiber membrane to form hydrogen bonding with PDOL and bis((trifluoromethyl)sulfonyl)imide anion, dramatically improving the mechanical strength, ionic conductivity, and transference number of GPE. Besides, molecular dynamic simulation is used to reveal the intrinsic factors of high ionic conductivity and reinforcing effect in the meantime. Consequently, the LiFePO4 //Li batteries using self-enhancing GPE show extraordinary cyclic stability over 800 cycles under high current density of 2 C, with a capacity decay of 0.021% per cycle, effectively suppressing the growth of lithium dendrites. This ingenious strategy is expected to manufacture advanced performance and high safety LMBs and compatible with the current battery production.

8.
ACS Appl Mater Interfaces ; 12(46): 51488-51498, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33147944

RESUMO

Though being a promising anode material for sodium-ion batteries (SIBs), MoS2 with high theoretical capacity shows poor rate capability and rapid capacity decay, especially involving the conversion of MoS2 to Mo metal and Na2S. Here, we report all-in-one MoS2 nanosheets tailored by porous nitrogen-doped graphene (N-RGO) for the first time to achieve superior structural stability and high cycling reversibility of MoS2 in SIBs. The all-in-one MoS2 nanosheets possess desirable structural characteristics by admirably rolling up all good qualities into one, including vertical alignment, an ultrathin layer, vacancy defects, and expanded layer spacing. Thus, the all-in-one MoS2@N-RGO composite anode exhibits an improvement in the charge transport kinetics and availability of active materials in SIBs, resulting in outstanding cycling and rate performance. More importantly, the restricted growth of all-in-one MoS2 by the porous N-RGO via a strong coupling effect dramatically improves the cycling reversibility of conversion reaction. Consequently, the all-in-one MoS2@N-RGO composite anode demonstrates excellent reversible capacity, outstanding rate capability, and superior cycling stability. This study strongly suggests that the all-in-one MoS2@N-RGO has great potential for practical application in high-performance SIBs.

9.
Chem Commun (Camb) ; 56(78): 11625-11628, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870203

RESUMO

Elastomer, poly(n-butyl methacrylate), coated liquid metal (LM) nanodroplets (EGaIn@PBMA) were successfully fabricated via a facile in situ free radical polymerization method. The as-prepared soft nanoparticles can be directly hot-pressed into nanocomposites which not only exhibited ultra-high stretching flexibility (>400%) but also excellent dielectric properties with remarkably suppressed dielectric loss, showing great promise in the flexible energy-storage field.

10.
Nanomaterials (Basel) ; 8(9)2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30200354

RESUMO

A surface-sizing technique was offered to take full advantage of multi-walled carbon nanotubes (MWCNTs) and epoxy resins. Two surface-sizing treated MWCNTs were obtained through a ball-milling treatment of amino-functionalized MWCNTs (MWCNT-NH2) with n-butyl glycidylether (BuGE) and benzyl glycidylether (BeGE). These were referred to as MWCNT-BuGE and MWCNT-BeGE. The results indicated that the surface sizing effectively enhanced wettability, dispersibility of MWCNTs in the epoxy resin. These ameliorating effects, along with improved interfacial interaction between MWCNT-BeGE containing benzene rings and the epoxy matrix, which can offer a more efficient local load-transfer from matrix to MWCNTs, as observed by a higher G-band shift in Raman spectrum under bending loads than that of MWCNT-BuGE reinforced ones. Correspondingly, MWCNT-BeGE/epoxy nanocomposites exhibited increasing flexural strength and modulus of 22.9% and 37.8% respectively compared with the neat epoxy, and 7.3% and 7.7% respectively compared with MWCNT-BuGE/epoxy nanocomposites with the same MWCNT content.

11.
RSC Adv ; 9(1): 377-388, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-35521567

RESUMO

Carbon fiber-reinforced polymer composites have been widely used in various fields and have inevitably produced large amounts of composite waste. The recycling of carbon fibers with high value has become an active research topic at related institutions and production enterprises. In this paper, the catalytic pyrolysis of T700 carbon fiber/epoxy composites in molten salt was studied. Due to the efficient solubility of molten ZnCl2 for the epoxy matrix and catalytic fracture of the C-N bonds by the action of Zn2+ ions, the epoxy composites can be completely degraded at 360 °C in 80 min under standard pressure, and the reclamation efficiency was significantly enhanced compared with conventional pyrolysis reclamation without a catalyst. The types and contents of the main oxygen-containing functional groups on the surfaces of the fibers reclaimed with ZnCl2 were similar to those of the virgin fibers, and the graphitization structure of the carbon fibers was not destroyed in the pyrolysis process. The tensile strength of a monofilament of the fibers reclaimed with ZnCl2 was obviously higher than that of fibers reclaimed in air; it reached a high retention rate that was about 95% that of the virgin fibers. The fibers reclaimed with ZnCl2 after sizing exhibited a desirable reinforcing effect on the flexure performance and interlaminar shear strength of unidirectional carbon fiber/epoxy composites which was close to the performance levels of composite samples containing commercial T700 carbon fibers. Therefore, efficient technology to reclaim high-quality carbon fibers from epoxy matrices has been devised.

12.
ACS Appl Mater Interfaces ; 10(1): 1093-1103, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29244950

RESUMO

Nowadays, physical absorption has become a feasible method offering an efficient and green route to remove organic pollutants from the industrial wastewater. Inspired by polydopamine (PDA) chemistry, one-dimensional PDA-functionalized multiwalled carbon nanotubes (MWCNT-PDA) were creatively introduced into graphene aerogel framework to synthesize a robust graphene/MWCNT-PDA composite aerogel (GCPCA). The whole forming process needed no additional reducing agents, significantly reducing the contamination emissions to the environment. The GCPCA exhibited outstanding repeatable compressibility, ultralight weight, as well as hydrophobic nature, which were crucial for highly efficient organic pollution absorption. The MWCNTs in moderate amounts can provide the composite aerogels with desirable structure stability and extra specific surface area. Meanwhile, the eventual absorption performance of GCPCAs can be improved by optimizing the microporous structure. In particular, a novel "cabbagelike" hierarchical porous structure was obtained as the prefreezing temperature was decreased to -80 °C. The miniaturization of pore size around the periphery of GCPCA enhanced the capillary flow in aerogel channels, and the super-absorption capacity for organic solvents was up to 501 times (chloroform) its own mass. Besides, the GCPCAs exhibited excellent reusable performance in absorption-squeezing, absorption-combustion, and absorption-distillation cycles according to the characteristic of different organic solvents. Because of the viable synthesis method, the resulting GCPCAs with unique performance possess broad and important application prospects, such as oil pollution cleanup and treatment of chemical industrial wastewater.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-749834

RESUMO

@#Objective    To evaluate the security and outcomes of thoracolaparoscopic esophagectomy (TLE) versus open approach (OA) for thoracic esophageal squamous cell carcinoma. Methods    From June 2014 to June 2015, 125 patients with thoracic esophageal squamous cell carcinoma underwent esophagectomy through McKeown approach, including TLE (a TLE group, 107 patients, 77 males and 30 females) and OA (an OA group, 18 patients, 13 males and 5 females). The data of operation and postoperative complications of the two groups were analyzed retrospectively. Results    There was no statistical difference in the duration of operation and ICU stay and resected lymph nodes around laryngeal recurrent nerve between the TLE group and the OA group (333.58±72.84 min vs. 369.17±91.24 min, P=0.067; 2.84±1.44 d vs. 6.44±13.46 d, P=0.272; 4.71±3.87 vs. 3.89±3.97, P=0.408) . There was a statistical difference in blood loss, total resected lymph nodes and resected lymph nodes groups between TLE group and OA group (222.62±139.77 ml vs. 427.78±276.65, P=0.006; 19.62±9.61 vs. 14.61±8.07, P=0.038; 3.70±0.99 vs. 3.11±1.13, P=0.024). The rate of postoperative complications was 32.7% in the TLE group and 38.9% in the OA group (P=0.608). There was a statistical difference (P=0.011) in incidence of pulmonary infection (2.8% in the TLE group and 16.7% in the OA group). Incidences of complications, such as anastomotic leakage, cardiac complications, left-side hydrothorax, right-side pneumothorax, voice hoarse and incision infection, showed no statistical difference between two groups. Conclusion    For patients with thoracic esophageal squamous cell carcinoma, TLE possesses advantages of more harvested lymph nodes, less blood loss and less pulmonary infection comparing with open approach, and is complied with the principles of security and oncological radicality of surgery.

14.
Chem Commun (Camb) ; 53(3): 521-524, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27917430

RESUMO

A facile synthesis of three-dimensional ultra-light (≈2.52 mg cm-3) graphene-poly(dopamine) modified carbon nanotube composite aerogels that needed no additional reducing agents during the forming process is reported herein. The composite aerogels exhibited highly repeatable compressibility and superior electrical conductivity, and thus will have an important application value in strain-sensitive functional devices.


Assuntos
Géis/química , Grafite/química , Indóis/química , Nanocompostos/química , Nanotubos de Carbono/química , Polímeros/química , Força Compressiva , Condutividade Elétrica , Modelos Moleculares , Nanocompostos/ultraestrutura , Nanotecnologia , Nanotubos de Carbono/ultraestrutura , Oxirredução , Porosidade
15.
Asian Pac J Cancer Prev ; 16(8): 3189-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25921119

RESUMO

BACKGROUND: To explore the expression of TS, RRM, ERCC1, TUBB3 and STMN1 genes in the tissues of patients with non-small cell lung cancer (NSCLC) and its significance in guiding the postoperative adjuvant chemotherapy. MATERIALS AND METHODS: Real time polymerase chain reaction (PCR) was applied to detect the expression of TS, RRM, ERCC1, TUBB3 and STMN1 genes in the tissues of NSCLC patients so as to analyze the relationship between the expression of each gene and the clinical characteristics and to guide the postoperative individualized chemotherapy according to the detection results of NSCLC patients. RESULTS: Expression of TS gene was evidently higher in patients with adenocarcinoma than those with non-adenocarcinoma (P=0.013) and so was the expression of ERCC1 (P=0.003). The expression of TUBB3 gene was obviously higher in NSCLC patients in phases I/II and IV than those in phase III (P1=0.021; P2=0.004), and it was also markedly higher in patients without lymph node metastasis than those with (P=0.008). The expression of STMN1 gene was apparently higher in patients in phase I/II than those in phase IV (P=0.002). There was no significant difference between the rest gene expression and the clinical characteristics of NSCLC patients (P>0.05). Additionally, the disease- free survival (DFS) was significantly longer in patients receiving gene detections than those without (P=0.021). CONCLUSIONS: The selection of chemotherapeutic protocols based singly on patients' clinical characteristics has certain blindness. However, the detection of tumor-susceptible genes can guide the postoperative adjuvant chemotherapy and prolong the DFS of NSCLC patients.


Assuntos
Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/secundário , Neoplasias Pulmonares/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Quimioterapia Adjuvante , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Pós-Operatórios , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonucleosídeo Difosfato Redutase , Estatmina/genética , Taxa de Sobrevida , Timidina Quinase/genética , Tubulina (Proteína)/genética , Proteínas Supressoras de Tumor/genética
16.
J Appl Toxicol ; 35(5): 500-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25224689

RESUMO

We recently reported that occupational exposure to trimethyltin (TMT) is a risk factor for developing kidney stones. To further examine the association between TMT exposure and the formation of kidney stones, we conducted a 180-day animal study and exposed the randomly grouped Sprague-Dawley (SD) rats to TMT in the drinking water at doses of 0, 8.2, 32.8 and 131.3 µg kg(-1) day(-1). Transient behavioral changes were observed in the high-dose group during the first 2 weeks of exposure. TMT exposure led to a significant dose-dependent inhibition of renal H(+)/K(+)-ATPase and an increase in urinary pH. In comparison to no kidney stones being identified in the control and the lowest dose group, 1 rat in the 32.8 µg kg(-1) day(-1) dose group and 3 out of 9 rats in the 131.3 µg kg(-1) day(-1) dose group were found to have stones in the kidney/urinary tract. Pathological analysis showed that more wide spread calcium disposition was observed in kidneys of rats with TMT exposure compared with the rats in the control group. However, X-ray diffraction (XRD) analysis found that the kidney stones were mainly composed of struvite with the formula: NH4MgPO4 6H2O, while calcium-containing components were also detected. Together, this study further demonstrates through animal studies that chronic exposure to a relatively low level of TMT induces nephrotoxicity and increases the risk for developing kidney stones.


Assuntos
Cálculos Renais/patologia , Compostos de Trimetilestanho/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Rim/efeitos dos fármacos , Rim/patologia , Cálculos Renais/induzido quimicamente , Compostos de Magnésio/toxicidade , Compostos de Magnésio/urina , Masculino , Fosfatos/toxicidade , Fosfatos/urina , Ratos , Ratos Sprague-Dawley , Estruvita , Compostos de Trimetilestanho/urina , Difração de Raios X
17.
Mol Med Rep ; 10(4): 2059-64, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25109624

RESUMO

Lung cancer is one of the most common and serious types of cancer, and is characterized by uncontrolled cell growth and metastasis from lung tissues to other body parts. The programmed cell death 5 (Pdcd5) protein is known to accelerate apoptosis in different cell types of tumor. The aim of the present study was to explore the role of Pdcd5 in lung carcinoma and to identify the mechanisms underlying the antitumorigenic properties of Pdcd5 in lung cancer. First, we detected and compared the expression of Pdcd5 in healthy and highly differentiated adenocarcinoma lung tissues. The results of histochemical staining and western blot analysis demonstrated that Pdcd5 expression is markedly decreased in highly differentiated lung adenocarcinoma. Next, we used the lung adenocarcinoma cell line A549 to study the effects of Pdc5 expression on proliferation and colony formation. The results revealed that the expression of Pdcd5 significantly inhibits cell proliferation and colony formation in A549 cells. Importantly, Pdcd5 expression induced tumor cell apoptosis, and the apoptotic proteins caspase-3 and -9 were activated. The expression of B-cell lymphoma 2 (Bcl-2) was reduced and that of Bcl2­associated X protein (Bax) was increased, overall suggesting that the intrinsic apoptotic pathway is activated. Furthermore, using a mice xenograft model and vectors for stable expression or silencing of Pdcd5, we showed that stable expression of the protein significantly increases the survival rate of mice in vivo (P<0.01 compared to control). In conclusion, both in vitro and in vivo experiments demonstrated that Pdcd5 expression inhibits proliferation and induces apoptosis in the A549 cell line, indicating that the Pdcd5 protein may play an important role in the progression of lung cancer. Therefore, Pdcd5 may be a promising target for the therapy of lung carcinoma.


Assuntos
Adenocarcinoma/patologia , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Neoplasias Pulmonares/patologia , Mitocôndrias/metabolismo , Proteínas de Neoplasias/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Animais , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Taxa de Sobrevida , Transplante Heterólogo , Proteína X Associada a bcl-2/metabolismo
18.
Bull Environ Contam Toxicol ; 90(5): 626-33, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23478947

RESUMO

Extensive uses of methyltin compounds in polyvinyl chloride (PVC) production have led to a dramatic increase of occupational-related methyltin poisoning accidents and the widespread contamination of methyltins in various environmental media. Here, we conducted studies to compare the acute toxicity induced by trimethyltin (TMT) and dimethyltin (DMT), and investigated the cumulative toxic effects of TMT in rats and mice. Neurobehavioral changes were observed in rats and mice treated with either DMT or TMT, but we also observed that both TMT and DMT exposure in rats significantly lowered the blood potassium level. Moreover, the cumulative toxic coefficient factor of TMT was 1.7 in rats versus 3.8 in mice, suggesting a high cumulative risk for rats and a moderate risk for mice. In summary, we demonstrated that acute and chronic exposure to methyltin compounds induced neurotoxicity and hypokalemia. Moreover, our study suggests that TMT can accumulate in the body and pose a risk for workers chronically exposed to a low dose of TMT.


Assuntos
Poluentes Ambientais/toxicidade , Compostos Orgânicos de Estanho/toxicidade , Animais , Feminino , Hipopotassemia/induzido quimicamente , Masculino , Camundongos , Síndromes Neurotóxicas , Ratos , Ratos Sprague-Dawley , Compostos de Trimetilestanho/toxicidade
19.
Artigo em Chinês | MEDLINE | ID: mdl-21941786

RESUMO

OBJECTIVE: To study the activity, protein and gene expression of renal HK-ATPase (HKA) in rats subchronic exposed to trimethyltin chloride (TMT). METHODS: In subchronic toxic test (14-week), 55 female SD rats (age, 6 weeks) were divided randomly into 5 groups: control, low, medium, high and super high dosage, respectively, which drank water with TMT of 0, 8.20, 32.81, 131.25 and 262.50 microg x kg(-1) x d(-1) for 14 weeks. Then serum K+ levels were measured; the activities of HK-ATPase (HKA) in kidneys were detected by the method of determinated phosphorus content; Western Blot assay and real-time PCR were used to exam the protein and mRNA expression levels of HKA in kidneys, respectively. RESULTS: The serum K+ level in super-high dosage group was (5.6 +/- 0.4) mmol/L, which was significantly lower than that [(6.9 +/- 0.3) mmol/L] in control group (P < 0.01). The HKA enzymatic activity of kidneys in low and super high dosage groups was 4.50 +/- 1.45 and 4.55 +/- 0.72 micromolPi x mg prot(-1)h(-1), respectively, which were significantly lower than that (6.55 +/- 0.77 micromol Pi x mg prot(-1) h(-1)) in control group (P < 0.05). CONCLUSION: When rats were exposed subchronic to TMT, the renal HKA activity could reduce, but the expression levels of HKA protein and mRNA did not decrease.


Assuntos
ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Compostos de Trimetilestanho/toxicidade , Animais , Feminino , Expressão Gênica , ATPase Trocadora de Hidrogênio-Potássio/genética , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
20.
Toxicology ; 271(1-2): 45-50, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20211677

RESUMO

Trimethyltin chloride (TMT), a byproduct of plastic stabilizers, has caused 67 poisoning accidents in the world; more than 98% (1814/1849) of the affected patients since 1998 have been in China. As a long-established toxic chemical, TMT severely affects the limbic system and the cerebellum; however, its relationship with hypokalemia, a condition observed in the majority of the cases in the last decade, remains elusive. To understand the mechanism underlying hypokalemia induced by TMT, Sprague-Dawley (SD) rats were administered TMT to determine the relationship between H(+)/K(+)-ATPase activity and the blood and urine K(+) concentration and pH, respectively. H(+)/K(+)-ATPase protein and mRNA were observed too. In vitro changes to intracellular pH, K(+) channels in renal cells were measured. The results showed that TMT increased potassium leakage from the kidney, raised urine pH, and inhibited H(+)/K(+)-ATPase activity both in vitro and in vivo. In the tested animals, H(+)/K(+)-ATPase activity was positively correlated with the decrease of plasma K(+) and blood pH but was negatively correlated with the increase of urine K(+) and urine pH (P<0.01), while TMT did not change the expression of H(+)/K(+)-ATPase protein and mRNA. TMT decreased intracellular pH and opened K(+) channels in renal intercalated cells. Our findings suggest TMT can directly inhibit the activity of H(+)/K(+)-ATPases in renal intercalated cells, reducing urine K(+) reabsorption and inducing hypokalemia.


Assuntos
Hipopotassemia/induzido quimicamente , Nefropatias/induzido quimicamente , Túbulos Renais Coletores/efeitos dos fármacos , Túbulos Renais Coletores/enzimologia , Inibidores da Bomba de Prótons , Compostos de Trimetilestanho/toxicidade , Animais , Western Blotting , Células Cultivadas , ATPase Trocadora de Hidrogênio-Potássio/genética , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Concentração de Íons de Hidrogênio , Hipopotassemia/enzimologia , Nefropatias/sangue , Nefropatias/enzimologia , Potássio/sangue , Potássio/urina , RNA Mensageiro/química , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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