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https://www.readbyqxmd.com/read/28738656/an-ultrasensitive-fluorescent-nanosensor-for-trypsin-based-on-upconversion-nanoparticles
#1
Mingmin Wu, Xiaoyong Wang, Kun Wang, Zijian Guo
Trypsin and its inhibitors are relevant to many physiological processes and diseases. In this study, a nanosensor capable of detecting trypsin and its inhibitors was designed based on the fluorescence resonance energy transfer (FRET) between upconversion nanoparticle (UCNP) and gold nanoparticle (AuNP). UCNP and AuNP were linked by a trypsin-sensitive peptide DDDDARC, forming the non-fluorescent UCNP-peptide-AuNP nanosensor. In the presence of trypsin, the peptide was cleaved and the quenched fluorescence was restored; in the presence of trypsin inhibitors, the recovery of the fluorescence was decreased...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738631/a-review-aptamer-based-analytical-strategies-using-the-nanomaterials-for-environmental-and-human-monitoring-of-toxic-heavy-metals
#2
REVIEW
Leila Farzin, Mojtaba Shamsipur, Shahab Sheibani
Recent developments in biotechnology offer the new methods for the sensitive detection of heavy metals based on the affinity and specificity of aptamers, as nucleic acid ligands selected from random sequence pools in vitro. Heavy metals have received considerable importance as the most toxic metallic pollutants which may cause serious environmental damages. They are classified as trace elements because of their presence in trace concentrations in various environmental matrices. Thus, the precise and sensitive methods to detect heavy metals are important to ensure human and environment safety...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738612/sorption-luminescence-method-for-determination-of-terbium-using-transcarpathian-clinoptilolite
#3
V O Vasylechko, G V Gryshchouk, V P Zakordonskiy, L O Vasylechko, M Schmidt, I M Leshchack, Ya M Kalychak, S R Bagday
Sorption-luminescent method for terbium determination based on natural Transcarpathian clinoptilolite without using of complex synthetic organic compounds and toxic solvents was proposed. Optimal luminophore preparation conditions are sorption of Tb(III) on zeolite in the borate buffer solution with pH 8.25 and further calcination of clinoptilolite-Tb(III) samples at 500°C. For luminescence excitation the rays with wavelength of λ = 220nm of were used. Luminescence intensity at λ = 545nm was selected as analytical parameter for a quantitative terbium determination...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738611/a-novel-electrochemical-sensor-based-on-wo3-nanorods-decorated-poly-sodium-4-styrenesulfonate-functionalized-graphene-nanocomposite-modified-electrode-for-detecting-of-puerarin
#4
Shasha Jing, Huijun Zheng, Li Zhao, Lingbo Qu, Lanlan Yu
An electrochemical sensing platform was fabricated based on composition of poly(sodium 4-styrenesulfonate) (PSS), graphene (GN) and WO3 nanorods on glassy carbon electrode (GCE). The PSS-GN/WO3 nanocomposite significantly increased the oxidative activity of puerarin due to the individual merit and mutual effect of PSS-GN and WO3 nanorods which improved the performance of the electrochemical sensor with high sensitivity. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) measurements were used for the detection of puerarin...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738606/a-label-free-fluorometric-assay-for-actin-detection-based-on-enzyme-responsive-dna-templated-copper-nanoparticles
#5
Quanwei Song, Lixia Yang, Hongkun Chen, Rong Zhang, Na Na, Jin Ouyang
Herein, we develop a fluorescent strategy for label-free detection of actin by the in situ formation of double-stranded DNA (dsDNA) templated copper nanoparticles (CuNPs) and the digestion capability of deoxyribonuclease I (DNase I). In this design, the introduction of actin can effectively hinder the enzymic digestion owing to the exceptional target-mediated conformational structure between actin and DNase I. Consequently, the remaining adenine-thymine-rich dsDNA can act as an efficient template for fluorescent CuNPs (λex = 340nm, λem = 585nm) with a Mega-Stokes shifting (245nm)...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738597/sensitive-detection-of-sulfide-based-on-the-self-assembly-of-fluorescent-silver-nanoclusters-on-the-surface-of-silica-nanospheres
#6
Yehan Yan, Kui Zhang, Huan Yu, Houjuan Zhu, Mingtai Sun, Tasawar Hayat, Ahmed Alsaedi, Suhua Wang
Hydrogen sulfide is a toxic and flammable gaseous pollutant often emitted to air as a by-product of water supply, chemical, petroleum and coal industries. It can be transferred into sulfur dioxide in the air under some meteorologic conditions. Herein, we report a novel ratiometric fluorescence method for hydrogen sulfide based on silver nanoclusters and quantum dots. The silver nanoclusters have been self-assemblied onto the surface of silica spheres, which are embedded with red fluorescent quantum dots, to form a dual-emissive nanohybrid...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738583/application-of-headspace-and-direct-immersion-solid-phase-microextraction-in-the-analysis-of-organothiophosphates-related-to-the-chemical-weapons-convention-from-water-and-complex-matrices
#7
Marc André Althoff, Andreas Bertsch, Manfred Metzulat, Thomas M Klapötke, Konstantin L Karaghiosoff
The successful application of headspace (HS) and direct immersion (DI) solid phase microextraction (SPME) for the unambiguous identification and characterization of a series of toxic thiophosphate esters, such as Amiton (I), from aqueous phases and complex matrices (e.g. grass and foliage) has been demonstrated. A Thermo Scientific gas chromatograph (GC) - tandem mass spectrometer (MS/MS) system with a TriPlus RSH® autosampler and a SPME tool was used to investigate the effect of different parameters that influence the extraction efficiency: e...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738577/high-bright-fluorescent-carbon-dot-as-versatile-sensing-platform
#8
Mumei Han, Liping Wang, Siheng Li, Liang Bai, Yunjie Zhou, Yue Sun, Hui Huang, Hao Li, Yang Liu, Zhenhui Kang
The surface functionalization will introduce additional functional groups on carbon dots (CDs) surface and then enrich the properties of CDs. Here, we show the various surface functionalized CDs (-COOH, -OH, -SH, -NH2, etc, named as NS-CDs) were synthesized with fascinating features, including high quantum efficiency (38.9%), long-term stability and good biocompatibility. Notably, it can serve as multifunction fluorescent probe in sensing system, including label-free detections in hydrogen peroxide (H2O2) with a wide linear range (1...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738557/multielemental-analysis-of-18-essential-and-toxic-elements-in-amniotic-fluid-samples-by-icp-ms-full-procedure-validation-and-estimation-of-measurement-uncertainty
#9
B Markiewicz, A Sajnóg, W Lorenc, A Hanć, I Komorowicz, J Suliburska, R Kocyłowski, D Barałkiewicz
Amniotic fluid is the substantial factor in the development of an embryo and fetus due to the fact that water and solutes contained in it penetrate the fetal membranes in an hydrostatic and osmotic way as well as being swallowed by the fetus. Elemental composition of amniotic fluid influences the growth and health of the fetus, therefore, an analysis of amniotic fluid is important because the results would indicate abnormal levels of minerals or toxic elements. Inductively coupled plasma mass spectroscopy (ICP-MS) is often used for determination of trace and ultra-trace level elements in a wide range of matrices including biological samples because of its unique analytical capabilities...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738528/molecular-basis-for-oxidative-stress-induced-by-simulated-microgravity-in-nematode-caenorhabditis-elegans
#10
Li Zhao, Qi Rui, Dayong Wang
Caenorhabditis elegans is an important in vivo assay system for toxicological studies. Herein, we investigated the role of oxidative stress and the underlying molecular mechanism for induced adverse effects of simulated microgravity. In nematodes, simulated microgravity treatment induced a significant induction of oxidative stress. Genes (mev-1, gas-1, and isp-1) encoding a molecular machinery for the control of oxidative stress were found to be dysregulated in simulated microgravity treated nematodes. Meanwhile, genes (sod-2, sod-3, sod-4, sod-5, aak-2, skn-1, and gst-4) encoding certain antioxidant defense systems were increased in simulated microgravity treated nematodes...
July 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28738522/combination-of-nrp1-mediated-irgd-with-5-fluorouracil-suppresses-proliferation-migration-and-invasion-of-gastric-cancer-cells
#11
Li Zhang, Yanfeng Xing, Qi Gao, Xuejun Sun, Di Zhang, Gang Cao
Gastric cancer is one of the most of common cancers in the world. 5-Fluorouracil (5-FU) has been identified as one of the standard first-line chemotherapy drugs for locally advanced or metastatic gastric cancer. However, poor tumor penetration, bad selectivity and toxic side effects are the major limitations for the application of chemotherapy drugs in anticancer therapy. Recently, plenty of studies demonstrate that the novel tumor-homing peptide iRGD could promote the tumor-penetrating capability of chemotherapy drugs in multiple cancers, and neuropilin-1 (NRP1) protein is the critical mediator for iRGD...
July 19, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28738510/degradation-kinetics-and-mechanism-of-sulfadiazine-and-sulfamethoxazole-in-an-agricultural-soil-system-with-manure-application
#12
Yu Zhang, Shuangqing Hu, Hongchang Zhang, Genxiang Shen, Zhejun Yuan, Wei Zhang
Recently, under the application of waste-water, manure and biosolids, antibiotics have been used massively in agriculture resulted in antibiotic resistance and potential environmental risks. In the present study, the removal of sulfadiazine (SDZ) and sulfamethoxazole (SMX) in an agricultural soil system was explored. All the experiments were conducted under different incubation conditions for 49days. The experimental results indicated that all the degradation processes could effectively follow a first-order kinetic model...
July 18, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28738497/oeanolic-acid-protects-against-the-hepatotoxicity-of-d-galactosame-plus-endotoxin-in-mice
#13
Xiao-Li Wan, Yuan-Fu Lu, Shang-Fu Xu, Qin Wu, Jie Liu
Oleanolic acid (OA) is a triterpenoid contained in many herbal medicines. The aim of this study was to investigate the protective effect of OA against D-galactosame plus lipopolysaccharides (D-GalN/LPS)-induced acute liver injury and the underling mechanisms. Mice were randomly divided into normal control with vehicles only (corn oil), D-GalN/LPS only (700mg/10μg/kg, ip), OA-po (200μmol/kg in corn oil, po) plus D-GalN/LPS, and OA-sc (50μmol/kg in 2% tween 80, sc) plus D-GalN/LPS groups. OA pretreatment was conducted twice daily for 4 consecutive days...
July 18, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28738424/use-of-high-throughput-in-vitro-toxicity-screening-data-in-cancer-hazard-evaluations-by-iarc-monograph-working-groups
#14
Weihsueh A Chiu, Kathryn Z Guyton, Matthew T Martin, David M Reif, Ivan Rusyn
Evidence regarding carcinogenic mechanisms serves a critical role in International Agency for Research on Cancer (IARC) Monograph evaluations. Three recent IARC Working Groups pioneered inclusion of the US Environmental Protection Agency (EPA) ToxCast program high-throughput screening (HTS) data to supplement other mechanistic evidence. In Monograph V110, HTS profiles were compared between perfluorooctanoic acid (PFOA) and prototypical activators across multiple nuclear receptors. For Monograph V112 -113, HTS assays were mapped to 10 key characteristics of carcinogens identified by an IARC expert group, and systematically considered as an additional mechanistic data stream...
July 24, 2017: ALTEX
https://www.readbyqxmd.com/read/28738305/contamination-characteristics-and-source-apportionment-of-methylated-pahs-in-agricultural-soils-from-yangtze-river-delta-china
#15
Weixiao Chen, Xinyi Wu, Haiyun Zhang, Jianteng Sun, Wenxin Liu, Lizhong Zhu, Xiangdong Li, Daniel C W Tsang, Shu Tao, Xilong Wang
Alkylated PAHs (APAHs) have been shown to be more toxic and persistent than their non-alkylated parent compounds. However, little is known about the extent of soil contamination by these pollutants. To help understand agricultural soil pollution by these compounds at a regional scale, a total of 18 methylated PAHs (MPAHs, a major class of APAHs) in 243 soil samples were analyzed. These soil samples were collected from 11 sites in the Yangtze River Delta (YRD) region, a representative fast developing area in China...
July 21, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28738303/bio-accumulation-of-lanthanum-from-lanthanum-modified-bentonite-treatments-in-lake-restoration
#16
G Waajen, F van Oosterhout, M Lürling
Lanthanum (La) modified bentonite (LMB) is one of the available mitigating agents used for the reduction of the phosphorus (P) recycling in eutrophic lakes. The potential toxicity of the La from LMB to aquatic organisms is a matter of concern. In this study the accumulation of La was investigated in the macrophyte Elodea nuttallii, in chironomid larvae and in several fish species during periods up to five years following in situ LMB applications. The application of LMB increased the La concentration of exposed plants and animals...
July 21, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28738294/oral-mucosa-dose-parameters-predicting-grade-%C3%A2-3-acute-toxicity-in-locally-advanced-nasopharyngeal-carcinoma-patients-treated-with-concurrent-intensity-modulated-radiation-therapy-and-chemotherapy-an-independent-validation-study-comparing-oral-cavity-versus
#17
Kaixin Li, Ling Yang, Qiang-Ying Hu, Xiao-Zhong Chen, Ming Chen, Yuanyuan Chen
PURPOSE: To determine whether volumes based on the contours of the mucosal surface instead of the oral cavity can be used to predict grade ≥3 acute oral mucosa toxicity in patients with locally advanced nasopharyngeal carcinoma (LANPC) treated with concurrent intensity-modulated radiation therapy (IMRT) and chemotherapy. METHODS AND MATERIALS: A standardized method for the oral cavity (oral cavity contours, OCC) and a novel method for the mucosal surface (mucosal surface contours, MSC) were developed for the oral mucosa and prospectively applied to the radiation treatment plans of 92 patients treated with concurrent IMRT and chemotherapy for LANPC...
July 21, 2017: Translational Oncology
https://www.readbyqxmd.com/read/28738271/heterogeneous-photocatalysis-of-tris-2-chloroethyl-phosphate-by-uv-tio2-degradation-products-and-impacts-on-bacterial-proteome
#18
Jinshao Ye, Juan Liu, Chongshu Li, Pulin Zhou, Shuang Wu, Huase Ou
The widespread, persistent and toxic organophosphorus esters (OPEs) have become one category of emerging environmental contaminants. Thus, it is in urgent need to develop a cost-effective and safe treatment technology for OPEs control. The current study is a comprehensive attempt to use UV/TiO2 heterogeneous photocatalysis for the degradation of a water dissolved OPEs, tris(2-chloroethyl) phosphate (TCEP). A pseudo-first order degradation reaction with a kobs of 0.3167 min(-1) was observed, while hydroxyl radical may be the dominating reactive oxidative species...
July 18, 2017: Water Research
https://www.readbyqxmd.com/read/28738258/open-label-multicentre-randomised-phase-ii-study-of-the-epssg-and-the-itcc-evaluating-the-addition-of-bevacizumab-to-chemotherapy-in-childhood-and-adolescent-patients-with-metastatic-soft-tissue-sarcoma-the-bernie-study
#19
Julia C Chisholm, Johannes H M Merks, Michela Casanova, Gianni Bisogno, Daniel Orbach, Jean-Claude Gentet, Anne-Sophie Thomassin-Defachelles, Pascal Chastagner, Stephen Lowis, Milind Ronghe, Kieran McHugh, Rick R van Rijn, Magalie Hilton, Jeanette Bachir, Sabine Fürst-Recktenwald, Birgit Geoerger, Odile Oberlin
PURPOSE: We evaluated the role of bevacizumab as part of the multi-modality treatment of children and adolescents with metastatic rhabdomyosarcoma (RMS) or non-rhabdomyosarcoma soft tissue sarcoma (NRSTS). PATIENTS AND METHODS: Eligible patients aged ≥6 months to <18 years were randomised to receive induction chemotherapy (four cycles of IVADo + five cycles of IVA, ±bevacizumab), surgery and/or radiotherapy, followed by maintenance chemotherapy (12 cycles of low-dose cyclophosphamide + vinorelbine, ±bevacizumab)...
July 21, 2017: European Journal of Cancer
https://www.readbyqxmd.com/read/28738256/p53-and-mitf-bcl-2-identified-as-key-pathways-in-the-acquired-resistance-of-nras-mutant-melanoma-to-mek-inhibition
#20
Ahmad Najem, Mohammad Krayem, François Salès, Nader Hussein, Bassam Badran, Caroline Robert, Ahmad Awada, Fabrice Journe, Ghanem E Ghanem
Activating mutations in Neuroblastoma RAS viral oncogene homolog (NRAS) are found in 15-30% of melanomas and are associated with a poor prognosis. Although MAP kinase kinase (MEK) inhibitors used as single agents showed a limited clinical benefit in patients with NRAS-mutant melanoma due to their rather cytostatic effect and high toxicity, their combination with other inhibitors of pathways known to cooperate with MEK inhibition may maximise their antitumour activity. Similarly, in a context where p53 is largely inactivated in melanoma, hyperexpression of Microphthalmia associated transcription factor (MITF) and its downstream anti-apoptotic targets may be the cause of the restraint cytotoxic effects of MEK inhibitors...
July 21, 2017: European Journal of Cancer
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