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1.
Phys Chem Chem Phys ; 21(35): 19288-19297, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31451821

RESUMO

This paper reports a facile, fast, and cost-effective method for the synthesis of three-dimensional (3D) porous AgNPs/Cu composites as SERS substrates for the super-sensitive and quantitative detection of food organic contaminations. Due to the 3D porous hotspot architecture and the strong plasmonic coupling between Ag and Cu, the porous AgNPs/Cu substrate achieves ultrasensitive detection of multiple analytes as low as 10-11 M (crystal violet, CV), 10-9 M (malachite green, MG), 10-11 M (acephate), and 10-9 M (thiram) even with a portable Raman device. Moreover, this 3D solid substrate has good signal uniformity (RSD < 11%) and superior stability (<14% signal loss), allowing for practical SERS detections. Importantly, by simply wiping the real sample surface using the substrate, it successfully detects CV and MG residues on crayfish, and the limit of detection (LOD) of CV and MG is determined to be 1.14 × 10-9 M and 0.94 × 10-7 M, respectively. Further, the substrate can also be applied to detect acephate on eggplant with a LOD of 1.41 × 10-9 M and thiram on an apple surface with a LOD of 1.04 × 10-7 M. Note that all these SERS detections on real samples have a broad dynamic concentration range and a good linear dependence. As a "proof of concept", multi-component detection on a real sample has also been demonstrated. This 3D solid substrate possesses excellent detection sensitivity, diversity, and accuracy, which allows rapid and reliable determination of toxic substances in foods.


Assuntos
Técnicas de Química Analítica/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Praguicidas/análise , Análise Espectral Raman , Animais , Técnicas de Química Analítica/economia , Cobre/química , Limite de Detecção , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/química
2.
ACS Sens ; 4(6): 1670-1681, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31117365

RESUMO

Semiconductor materials have become competitive candidates for surface-enhanced Raman scattering (SERS) substrates; however, their limited SERS sensitivity hinders the practical applications of semiconductors. Here, we develop a hybrid substrate by integrating anatase/rutile TiO2 heterostructure with dense plasmonic hotspots of Ag nanoparticle (AgNPs) for efficient photoinduced enhanced Raman spectroscopy (PIERS). The PIERS mechanism is systematically investigated by means of a portable Raman instrument. When ultraviolet (UV) light irradiates the substrate, the TiO2-Ag hybrid arrays produce remarkable charge-transfer enhancement, which can be ascribed to the highly efficient charge separation driven by heterojunction and transfer from TiO2 heterostructure to AgNPs. This platform allows for the rapid detection of multifold organic species, including malachite green (MG), crystal violet (CV), rhodamine 6G (R6G), thiram, and acephate, and as high as 27.8-fold enhancement over the normal SERS is achieved, representing the highest PIERS magnification up to the present time. The intensive PIERS enhancement makes it ultrasensitively detect analyte concentration of an order of magnitude lower than that of SERS method. The improved sensitivity and resolution can be readily realized by simple UV irradiation, which represents a major advantage of our PIERS methodology. Besides, the integration of uniform TiO2 heterostructure arrays with AgNPs generates superior signal reproducibility with relative standard deviation (RSD) value of less than 14%. In addition, the detected molecules on the substrate can be eliminated by photocatalytic degradation after PIERS measurements by using UV irradiation, which makes the substrate reusable for 15 cycles. The ultrahigh sensitivity, superior reproducibility, and excellent recyclability displayed by our platform may provide new opportunities in field detection analysis coupled with a portable Raman instrument.

3.
Sci Total Environ ; 672: 192-200, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30954818

RESUMO

As one of the largest man-made reservoir, the Three Gorges Reservoir (TGR) brings great uncertainty and challenges regarding trace metal (e.g., Cu) remobilization in the sediment. Therefore, in this study, sediment cores were collected from the mainstream of the Yangtze River and its three tributaries in the TGR, with a focus on evaluating the Cu remobilization risk and release dynamics using conventional methods, diffusive gradients in thin films (DGT), and the DGT-induced fluxes in sediments (DIFS) model. The results showed that although total Cu concentrations were slightly higher than background values, Cu was mainly observed in the unreactive residual fraction. Additionally, assessment of sediment quality guidelines and the risk assessment code indicated low Cu contamination risk for all sampling sites. However, the results of DGT measurements at the sediment-water interface showed efflux of Cu from sediment to the overlying water at most sites, except for the upstream of the Meixi River and the mainstream of the Yangtze River. Interestingly, diffusion fluxes at the three tributaries displayed an increase trend from the upper to lower reaches. The DIFS model simulation further implied that the highest resupply capacity and desorption rate occurred in the Zhuyi River and the upstream of the Meixi River. In fact, the accumulation of Cu from the upper to the lower reaches of the Zhuyi River significantly elevated the Cu resupply capacity. Thus, more attention should be paid to Cu mobilization in the TGR, especially in the Zhuyi River and the upstream of the Meixi River.

4.
BMC Vet Res ; 15(1): 113, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975135

RESUMO

BACKGROUND: In May 2017, 17 dogs in a German Shepherd breeding kennel in northern China developed respiratory clinical signs. The owner treated the dogs with an intravenous injection of Shuang-Huang-lian, a traditional Chinese medicine, and azithromycin. The respiratory signs improved 3 days post-treatment, however, cysts were observed in the necks of eight dogs, and three of them died in the following 2 days. CASE PRESENTATION: Quantitative real-time PCR was used to detect canine influenza virus (CIV). All of the dogs in this kennel were positive and the remaining 14 dogs had seroconverted. Two of the dogs were taken to the China Agricultural University Veterinary Teaching Hospital for further examination. Two strains of influenza virus (A/canine/Beijing/0512-133/2017 and A/canine/Beijing/0512-137/2017) isolated from the nasal swabs of these dogs were sequenced and identified as avian-origin H3N2 CIV. For the two dogs admitted to the hospital, hematology showed mild inflammation and radiograph results indicated pneumonia. Cyst fluid was plated for bacterial culture and bacterial 16 s rRNA gene PCR was performed, followed by Sanger sequencing. The results indicated an Enterococcus faecalis infection. Antimicrobial susceptibility tests were performed and dogs were treated with enrofloxacin. All 14 remaining dogs recovered within 16 days. CONCLUSIONS: Coinfection of H3N2 CIV and Enterococcus faecalis was detected in dogs, which has not been reported previously. Our results highlight that CIV infection might promote the secondary infection of opportunistic bacteria and cause more severe and complicated clinical outcomes.


Assuntos
Coinfecção/veterinária , Doenças do Cão/virologia , Infecções por Bactérias Gram-Positivas/veterinária , Vírus da Influenza A Subtipo H3N2 , Infecções por Orthomyxoviridae/veterinária , Animais , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/virologia , Surtos de Doenças/veterinária , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Cães/virologia , Enterococcus faecalis , Feminino , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/microbiologia , Vírus da Influenza A Subtipo H3N2/genética , Masculino , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
5.
Environ Pollut ; 249: 676-685, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30933765

RESUMO

Economic development puts pressure on environment through air, water and land degradation, which in turn brings real costs to the economy. Actual economy growth should therefore consider the environmental degradation cost resulted from economic activities. Pearl River Delta (PRD) region as a typical delta area with rapid development in China, is with great significance to understand the loses resulted from environmental pollution. This study conducts an environmental economic accounting within the PRD region from 2011 to 2015 using the environmental degradation cost accounting approach. We identified and calculated the economic, agricultural, industrial and social losses resulting from air, water and waste pollution with different valuation methods, which includes shadow price, replacement costs, market value method, etc. The results showed the total environmental degradation cost ranged from 18.1 to 19.8 billion US$ and the environmental degradation index declined slightly over the years, with significant differences among cities. It implied that the environmental condition of PRD region has been continuously improved over the years, but the capacity of environment control between cities had large differences. Cities in PRD region should therefore take measures tailored to their current situation to optimize their resource endowment and industrial structure, to overcome the conflicts between economic development and environmental protection. For cities with relatively high degradation cost, it is urgent to accelerate the efforts in improving the quality of the environment and ecosystem. For cities with lower degradation cost, it is important to take actions to keep on a sustainable and ecological efficient developing path. MAIN FINDINGS: The total environmental degradation cost of the PRD region is firstly calculated with insights on environmental management.


Assuntos
Conservação dos Recursos Naturais/métodos , Desenvolvimento Econômico , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Rios/química , Agricultura , China , Cidades , Conservação dos Recursos Naturais/economia , Ecossistema , Monitoramento Ambiental/economia , Poluição Ambiental/economia , Indústrias
6.
Cell Mol Gastroenterol Hepatol ; 7(4): 763-781, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30831319

RESUMO

BACKGROUND & AIMS: Obesity promotes the development of nonalcoholic fatty liver diseases (NAFLDs), yet not all obese patients develop NAFLD. The underlying causes for this discrepancy remain elusive. LPGAT1 is an acyltransferase that catalyzes the remodeling of phosphatidylglycerol (PG), a mitochondrial phospholipid implicated in various metabolic diseases. Here, we investigated the role of LPGAT1 in regulating the onset of diet-induced obesity and its related hepatosteatosis because polymorphisms of the LPGAT1 gene promoter were strongly associated with susceptibility to obesity in Pima Indians. METHODS: Mice with whole-body knockout of LPGAT1 were generated to investigate the role of PG remodeling in NAFLD. RESULTS: LPGAT1 deficiency protected mice from diet-induced obesity, but led to hepatopathy, insulin resistance, and NAFLD as a consequence of oxidative stress, mitochondrial DNA depletion, and mitochondrial dysfunction. CONCLUSIONS: This study identified an unexpected role of PG remodeling in obesity, linking mitochondrial dysfunction to NAFLD.

7.
Cell Biol Toxicol ; 35(5): 407-421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30680600

RESUMO

The goal of cancer eradication has been overshadowed despite the continuous improvement in research and generation of novel cancer therapeutic drugs. One of the undeniable existing problems is drug resistance due to which the paradigm of killing all cancer cells is ineffective. Tumor microenvironment plays a crucial role in inducing drug resistance besides cancer development and progression. Recently, many efforts have been devoted to understand the role of tumor microenvironment in cancer drug resistance as it provides the shelter, nutrition, and paracrine niche for cancer cells. Cancer-associated fibroblasts (CAFs), one major component of tumor microenvironment, reside in symbiotic relationship with cancer cells, supporting them to survive from cancer drugs. The present review summarizes the recent understandings in the role of CAFs in drug resistance in various tumors. Acknowledging the fact that drug resistance depends not only upon cancer cells but also upon the microenvironment niche could guide us to formulate novel cancer drugs and provide the optimal cancer treatment.

8.
Electrophoresis ; 40(4): 530-538, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30548630

RESUMO

An organic-silica hybrid monolith was prepared by a single-step ring-opening polymerization of octaglycidyldimethylsilyl polyhedral oligomeric silsesquioxane (POSS-epoxy), polyethylenimine (PEI), and ß-cyclodextrin (ß-CD) in a ternary porogenic solvent consisting of polyethylene glycol, 1,4-butanediol, and 1-propanol. The framework of POSS-PEI hybrid monolith could offer well-defined 3D skeleton, while ß-CD with the ability of forming a host-guest inclusion complexes with a variety of compounds could show an ability of specific selection. The obtained hybrid monoliths were successfully applied for separation of phenols, benzoic acids, and nucleobases. Especially due to the introduction of ß-CD, positional isomers including hydroquinone and resorcinol, o-nitrophenol and p-nitrophenol, as well as p-chlorophenol and o-chlorophenol were baseline separated and the column efficiency reached 82 300 plates/m for hydroquinone.

9.
Emerg Infect Dis ; 25(1): 161-165, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407904

RESUMO

During 2012-2017, we collected throat swabs from dogs in China to characterize canine influenza virus (CIV) A(H3N2) isolates. A new antigenically and genetically distinct CIV H3N2 clade possessing mutations associated with mammalian adaptation emerged in 2016 and replaced previously circulating strains. This clade probably poses a risk for zoonotic infection.


Assuntos
Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/virologia , Infecções por Orthomyxoviridae/veterinária , Animais , Variação Antigênica , China , Cães , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Infecções por Orthomyxoviridae/virologia , Filogenia , Zoonoses
10.
ACS Sens ; 3(11): 2446-2454, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30335972

RESUMO

It is urgent to develop a rapid, reliable, and in-site determination method to detect or monitor trace amounts of toxic substances in the field. Here, we report an alternative surface-enhanced Raman scattering (SERS) method coupled with a portable Raman device on a plasmonic three-dimension (3D) hot spot sensing surface. Plasmonic Ag nanoparticles (AgNPs) were uniformly deposited on 3D TiO2 nanopore arrays as a sensitive SERS substrate, and further coated with graphene oxide (GO). We demonstrate the plasmon-induced SERS enhancement (5.8-fold) and the improvement of catalytic activity by incorporation of plasmonic AgNPs into the 3D TiO2 nanopore arrays. The modification of GO on the TiO2-Ag nanopore array further increases by a 6.2-fold Raman enhancement compared to TiO2-Ag while maintaining good uniformity (RSD < 10%). The optimized TiO2-Ag-GO substrate shows powerful quantitative detection potential for drug residues in fish scales via a simple scrubbing method, and the limit of detection (LOD) for crystal violet (CV) was 10-8 M. The SERS substrate also showed detection practicability of pesticide residues in banana peel with an LOD of 10-7 M. In addition, our TiO2-Ag-GO substrate exhibits excellent SERS self-monitoring performance for catalytic reduction of multiple organics in NaBH4 solution, and the substrate shows good recyclability of 6 cycles. Such a 3D TiO2-Ag-GO substrate is a promising SERS substrate with good sensitivity, uniformity, and reusability, and may be utilized for further miniaturization for point of analytical applications.

11.
J Cell Mol Med ; 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30338905

RESUMO

Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiovascular disease. Although some genes and miRNAs related with HCM have been studied, the molecular regulatory mechanisms between miRNAs and transcription factors (TFs) in HCM have not been systematically elucidated. In this study, we proposed a novel method for identifying dysregulated miRNA-TF feed-forward loops (FFLs) by integrating sample matched miRNA and gene expression profiles and experimentally verified interactions of TF-target gene and miRNA-target gene. We identified 316 dysregulated miRNA-TF FFLs in HCM, which were confirmed to be closely related with HCM from various perspectives. Subpathway enrichment analysis demonstrated that the method was outperformed by the existing method. Furthermore, we systematically analysed the global architecture and feature of gene regulation by miRNAs and TFs in HCM, and the FFL composed of hsa-miR-17-5p, FASN and STAT3 was inferred to play critical roles in HCM. Additionally, we identified two panels of biomarkers defined by three TFs (CEBPB, HIF1A, and STAT3) and four miRNAs (hsa-miR-155-5p, hsa-miR-17-5p, hsa-miR-20a-5p, and hsa-miR-181a-5p) in a discovery cohort of 126 samples, which could differentiate HCM patients from healthy controls with better performance. Our work provides HCM-related dysregulated miRNA-TF FFLs for further experimental study, and provides candidate biomarkers for HCM diagnosis and treatment.

12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 32(8): 984-988, 2018 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-30238722

RESUMO

Objective: To explore the effectiveness of maintaining the stability between the fourth and the fifth metacarple base during the treatment in the hamate-metacarpal joint injury. Methods: Between September 2015 and June 2017, 13 cases of hamate-metacarpal joint injury were treated, including 12 males and 1 female, aged from 17 to 55 years (mean, 30.8 years). The injury causes included heavy boxing in 10 cases and falling in 3 cases. There were 2 cases of simple fourth metacarpal basal fracture, 1 basal fracture of the fourth metacarpal bone combined with intermetacarpal ligament fracture, 7 fractures of the fourth and fifth metacarpal base, 2 fourth metacarpal basal fractures combined with the fifth metacarpal basal fracture dislocation, and 1 base fracture of fourth and fifth metacarpal bone combined with hamate bone fracture. The time from injury to operation was 5-11 days (mean, 7.2 days). According to different damage degree and stability change between the fourth and the fifth metacarple base, a preliminary classification was made for different degrees of injury: 2 cases of type Ⅰ, 1 case of type Ⅱ, 7 cases of type Ⅲ, 2 cases of type Ⅳ, and 1 case of type Ⅴ. The patients were treated with corresponding internal fixation methods under the principle of stability recovery between the fourth and fifth metacarple base. Results: All the incisions healed by first intention without infection or skin necrosis. All the 13 patients were followed up 6-18 months with an average of 9.4 months. All fractures healed clinically, and the healing time was 5.5-8.0 weeks with an average of 6.3 weeks. No complication such as plate breakage, fracture dislocation, fracture malunion, and bone nonunion occurred. Hand function was evaluated according to the total active motion (TAM) functional evaluation standard of hand surgery at 6 months after operation, and the results was excellent in 9 cases, good in 3 cases, and fair in 1 case, with an excellent and good rate of 92.3%. Conclusion: Stability between the fourth and fifth metacarple base is of great significance to the classification and the treatment of the hamate-metacarpal joint injury.

13.
Science ; 361(6402): 582-585, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-29976797

RESUMO

Conventional theory predicts that ultrahigh lattice thermal conductivity can only occur in crystals composed of strongly bonded light elements, and that it is limited by anharmonic three-phonon processes. We report experimental evidence that departs from these long-held criteria. We measured a local room-temperature thermal conductivity exceeding 1000 watts per meter-kelvin and an average bulk value reaching 900 watts per meter-kelvin in bulk boron arsenide (BAs) crystals, where boron and arsenic are light and heavy elements, respectively. The high values are consistent with a proposal for phonon-band engineering and can only be explained by higher-order phonon processes. These findings yield insight into the physics of heat conduction in solids and show BAs to be the only known semiconductor with ultrahigh thermal conductivity.

14.
J Environ Sci (China) ; 70: 106-123, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30037397

RESUMO

The atmospheric deposition of heavy metals poses serious risks to the ecological system and human health. To advance our knowledge of atmospheric dry/wet heavy metal deposition in the PRD region, monthly fluxes were examined based on soluble/insoluble fractions of five heavy metal elements (Cu, Pb, Cd, Cr and Zn) in samples collected from January 2014 to December 2015 at Guangzhou (urban) and Dinghushan (suburban) sites. The ratios of wet/dry deposition fluxes indicated that heavy metal deposition was governed by wet deposition rather than dry deposition in the PRD region. Affected by the shifting of the Asian monsoon, wet deposition fluxes exhibited significant seasonal variation between summer monsoon seasons (April to September) and winter monsoon seasons (October to February) in this region. Cd was classified as an extremely strong potential ecological risk based on solubility and the Hakanson ecological risk index. Source contributions to wet deposition were calculated by PMF, suggesting that dust, biomass burning, industries, vehicles, long-range transport and marine aerosol sources in Guangzhou, and Zn fertilizers, marine aerosol sources, agriculture, incense burning, biomass burning, vehicles and the ceramics industry in Dinghushan, were the potential sources of heavy metals.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metais Pesados/análise , China , Poeira , Ecossistema , Rios
15.
IEEE Trans Cybern ; 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30040669

RESUMO

Combinatorial multiobjective optimization problems (CMOPs) are very popular due to their widespread applications in the real world. One common method for CMOPs is Pareto local search (PLS), a natural extension of single-objective local search (LS). However, classical PLS tends to reserve all of the nondominated solutions for LS, which causes the inefficient LS, as well as unbearable computational and space cost. Due to the aforementioned reasons, most PLS approaches can only handle CMOPs with no more than two objectives. In this paper, by combining the Pareto dominance and weighted sum (WS) approach in a grid system, the grid weighted sum dominance (gws-dominance) is proposed and integrated into PLS for CMOPs with multiple objectives. In the grid system, at most one representative solution is maintained in each grid for more efficient LS, thus largely reducing the computational and space complexity. The grid-based WS approach can further guide the LS in different grids for maintaining more widely and uniformly distributed Pareto front approximations. In the experimental studies, the grid WS PLS is compared with the classical PLS, three decomposition-based LS approaches [multiobjective evolutionary algorithm based on decomposition-LS (WS, Tchebycheff, and penalty-based boundary intersection)], a grid-based algorithm (ε-MOEA), and a state-of-the-art hybrid approach (multiobjective memetic algorithm based on decomposition) on two sets of benchmark CMOPs. The experimental results show that the grid weighted sum Pareto local search significantly outperforms the compared algorithms and remains effective and efficient on combinatorial multiobjective and even many-objective optimization problems.

16.
BMC Endocr Disord ; 18(1): 41, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921267

RESUMO

BACKGROUND: Pheochromocytoma, especially for noncatecholamine-secreting pheochromocytoma, is an extremely rare cause of ectopic corticotrophin-releasing hormone (CRH) syndrome. CASE PRESENTATION: A 27-year-old Chinese woman was administered dexamethasone for a skin allergy, but her general condition rapidly deteriorated over a month. She was subsequently hospitalized for typical clinical features of Cushing's syndrome. Endocrinological investigation confirmed severe hypercortisolism along with elevated plasma adrenocorticotropin hormone (ACTH). However, magnetic resonance imaging (MRI) revealed no pituitary adenoma. Abdominal contrast-enhanced computed tomography (CT) revealed a 6.5 cm heterogeneous right adrenal mass with mildly contrast enhancement. The tumor was found during a routine physical check-up at a local hospital 16 months ago; however, the patient did not have any symptoms and did not seek further medical attention at that time. Laparoscopic resection of the right adrenal tumor led to a rapid remission of Cushing's syndrome. Based on pathological findings and the presence of normal catecholamine metabolites in her serum and urine, the patient was diagnosed with noncatecholamine-secreting pheochromocytoma. Immunohistochemical staining of the adrenal tumor revealed positive staining for CRH and negative staining for ACTH. CONCLUSIONS: This is an extremely rare case of ectopic CRH syndrome caused by an adrenal noncatecholamine-secreting pheochromocytoma. Both ectopic ACTH syndrome and ectopic CRH syndrome should be considered in patients presenting with ACTH-dependent Cushing's syndrome caused by extrapituitary diseases.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Hormônio Liberador da Corticotropina/metabolismo , Síndromes Endócrinas Paraneoplásicas/etiologia , Feocromocitoma/complicações , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Feminino , Humanos , Imuno-Histoquímica , Feocromocitoma/metabolismo , Feocromocitoma/patologia
17.
J Exp Clin Cancer Res ; 37(1): 93, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29712569

RESUMO

BACKGROUND: The application of VEGF signaling inhibitors have been associated with more invasive or metastatic behavior of cancers including hepatocellular carcinoma (HCC). We explored the contribution of MET pathway to the enhanced HCC invasion and metastasis by VEGF signaling inhibition, and investigated the antitumor effects of NZ001, a novel dual inhibitor of MET and VEGFR2, in HCC. METHODS: Immunocompetent orthotopic mice model of hepal-6 was established to investigate the effects of either VEGF antibody alone or in combination with the selective MET inhibitor on tumor aggressiveness. The antitumor effects of NZ001 were examined in cultured HCC cells as well as in vivo models. MET gene amplification was determined by SNP 6.0 assay. MET/P-MET expression was detected by IHC. RESULTS: Selective VEGF signaling inhibition by VEGF antibody significantly reduced in vivo tumor growth of the orthotopic mice models, simultaneously also enhanced tumor invasion and metastasis, but inhibiting MET signaling attenuated this side-effect. Further study revealed that hypoxia caused by VEGF signaling inhibition induced HIF-1α nuclear accumulation, subsequently leading to elevated total-MET expression, and synergized with HGF in inducing invasion. NZ001, a novel dual inhibitor of MET and VEGFR2, markedly inhibited both tumor growth and metastasis of HCC, which showed obvious advantages over sorafenib in not inducing more invasive and metastatic behaviors. This effect is more pronounced in HCC with MET amplification and overexpression. CONCLUSIONS: The activation of MET is responsible for the metastasis-promoting effects induced by VEGF inhibition. MET and VEGFR2 dual blockade, NZ001, has advantages over sorafenib in not inducing more invasive and metastatic behaviors; MET amplification and overexpression can be used to identify the subgroup of patients most likely to get the optimal benefit from NZ001 treatment.

18.
Sci Rep ; 8(1): 7186, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739957

RESUMO

The nonlinear response of output-input microwave power for DMSO-ethanol mixture, which was exhibited as the direct evidence of non-thermal effect in experiment, was investigated by molecular dynamics simulation. Effects of microwave field on the mixture were evaluated from the alteration in structure, transport, hydrogen bonding dynamics and intermolecular interaction energy. Increasing the strength of the microwave field did not lead to any markedly conformational change, but decrease the diffusion coefficient. Prolonged hydrogen bonding lifetimes, which caused by the redistribution of microwave energy, was also detected. Distinct threshold effect was observed, which was consistent with the behavior in the experiment.

19.
Sensors (Basel) ; 18(5)2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29734738

RESUMO

We present a microwave method for the dielectric characterization of small liquids based on a metamaterial-based sensor The proposed sensor consists of a micro-strip line and a double split-ring resonator (SRR). A large electric field is observed on the two splits of the double SRRs at the resonance frequency (1.9 GHz). The dielectric property data of the samples under test (SUTs) were obtained with two measurements. One is with the sensor loaded with the reference liquid (REF) and the other is with the sensor loaded with the SUTs. Additionally, the principle of extracting permittivity from measured changes of resonance characteristics changes of the sensor loaded with REF and SUTs is given. Some measurements were carried out at 1.9 GHz, and the calculated results of methanol⁻water mixtures with different molar fractions agree well with the time-domain reflectometry method. Moreover, the proposed sensor is compact and highly sensitive for use of sub-wavelength resonance. In comparison with literature data, relative errors are less than 3% for the real parts and 2% for the imaginary parts of complex permittivity.

20.
Chemosphere ; 204: 310-317, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29665534

RESUMO

The stability of biochar is a major determinant of its potential for carbon sequestration. In previous studies, the biochar stability was evaluated by analyzing the oxidation resistance property of biochar, for which, K2Cr2O7/H2O2 oxidation and thermogravimetric analysis (TGA) were widely used to measure the high oxidation resistance of biochars. In this study, rice straw (RI)- and swine manure (SW)-derived biochars produced at different heating treatment temperatures (HTTs) and their corresponding de-ashed biochars and iron-biochars were selected to investigate the effect of minerals on these biochars stability. There was a significantly positive correlation between carbon remaining values (CRVs) obtained after K2Cr2O7/H2O2 oxidation and ash (mineral) contents of biochars (p < 0.05). Moreover, the decreasing CRVs of most biochars were observed after de-ashing treatment. These K2Cr2O7/H2O2 oxidation results indicated that endogenous minerals in biochars can protect biochars from chemical oxidation. On the other hand, the R50 (C recalcitrance index) values of iron-biochars (33.3-57.4%) were lower than those of corresponding biochars (38.6-60.8%), indicating that Fe-bearing mineral formed in biochars can promote the thermal decomposition of biochars. In H2O2 oxidation, the different change trend of CRVs between biochars produced at 450 °C and biochars produced at 600 °C after iron mineral treatment showed that the effect of exogenous Fe-bearing mineral on biochar stability was related to biochar category regulated by HTTs. This study indicated that endogenous minerals could increase biochar stability, and exogenous Fe-bearing minerals had dissimilar effects on different kinds of biochars, which critically regulates the potential of biochar for long-term carbon sequestration.


Assuntos
Carvão Vegetal/química , Esterco/análise , Minerais/química , Animais , Sequestro de Carbono , Oryza , Oxirredução , Suínos , Temperatura Ambiente
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