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BIOCELL 2024年第6期48卷 971-980页

作者： HONGBIAO WU DONGFANG LIU department of Colorectal and anal Surgery Ningbo First HospitalNingbo315010China

Background:Colorectal cancer(CRC)represents a substantial risk to public ***,theﬁrst US FDA-approved antiangiogenic drug(AAD)for human CRC treatment,faces resistance in *** role of lipid metabolism,particularly through OPA3-regulated lipid droplet production,in overcoming this resistance is under ***:The protein expression pattern of OPA3 in CRC primary/normal tissues was evaluated by bioinformatics ***3-overexpressed SW-480 and HCT-116 cell lines were established,and bevacizumab resistance and OPA3 effects on cell malignancy were ***3 protein/mRNA expression and lipid droplet-related genes were measured with Western blot and ***3 subcellular localization was detected using immunoﬂ*** and apoptosis were assessed via colony formation andﬂow *** formation assays were conducted to assess the angiogenic potential of human umbilical vein endothelial cells(HUVECs).Lipid analysis was used to measure the phosphatidylcholine(PC)and lysophosphatidylcholine(LPC)levels in CRC ***:Bioinformatics analysis revealed that OPA3 was downregulated in *** of OPA3 inhibited CRC cell proliferation,stimulated apoptosis,and suppressed the angiogenic ability of ***3 effectively reversed the resistance of CRC cells to bevacizumab and decreased lipid droplet production in CRC ***,OPA3 reversed the bevacizumab-induced lipid droplet production in CRC cells,thereby increasing CRC cell sensitivity to bevacizumab ***:This study suggests that OPA3 modulates lipid metabolism in CRC cells and reduces resistance to bevacizumab in CRC ***,OPA3 may be a potential therapeutic target against the AAD resistance in CRC.

关键词： Colorectal cancer OPA3 Bevacizumab Lipid droplet Antiangiogenic drug

Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

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Nano Research 2023年第5期16卷 7470-7480页

作者： Pablo Purohit Francisco J.Fortes Javier Laserna UMALASERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

determination of sildenafil by preconcentration on surfactant coated polymeric resin followed by spectrofluorimetry

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Journal of Pharmaceutical analysis 2013年第3期3卷 173-179页

作者： Chien C.Wang Roxana A.Gómez Liliana P.Fernandez INquISAL-CONICET Chacabuco y Pedernera5700-San LuisArgentina departamento de Farmacia Facultad de QuímicaBioquímica y FarmaciaUniversidad Nacional de San LuisArgentina rea de química analítica Facultad de QuímicaBioqímica y FarmaciaUniversidad Nacional de San LuisArgentina

The illicit addition of phosphodiesterase type-5 （Pde-5） inhibitors like sildenafil （Viagra） in product offered as herbal medicine or dietary supplement for male erectile dysfunction has concerned authorities in recent times. In this paper, we proposed a sensitive surfactant-coated Amberlite XADTM resin for sildenafil preconcentration method with spectrofluorimetric detection. Retention capacity of micellar coated XAD resin for sildenafil was studied and the obtained eluate was measured by spectrofluorometer at excitation and emission wavelengths of 350 and 430 nm, respectively. This method allowed the detection of sildenafil at 0.15 ng/mL with linear range of 0.0003-7.0 μg/mL. The method has been successfully applied to the analysis of some local commercially available herbal medicines and urine.

关键词： Sildenafil Herbal medicines Spectrofluorimetricanalysis Surfactant

Statistical evaluation of fluoride contamination in groundwater resources of Santiago del Estero Province, Argentina

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Geoscience Frontiers 2020年第6期11卷 2197-2205页

作者： K.Rondano Gómez C.E.López Pasquali G.Paniagua González P.Fernández Hernando R.M.Garcinuño Martínez departamento de Ciencias Básicas Facultad de Ciencias ForestalesUniversidad Nacional de Santiago Del EsteroArgentina departamento de Ciencias analíticas Facultad de CienciasUniversidad Nacional de Educación a DistanciaSpain departamento de química analítica Facultad de Agronomía y AgroindustriasUniversidad Nacional de Santiago Del EsteroArgentina

This study investigates the suitability of statistical techniques for evaluating the fluoride content and the groundwater quality from Robles department(RD)and Banda department(BD)in Santiago del Estero(Argentina).For the original statistical study,evaluation of nine parameters(fluoride,pH,conductivity,atmospheric and water temperature,total dissolved solids,chloride,hardness,and alkalinity)of 110 collected underground water samples from 23 dispersed rural areas was *** samples were obtained by sampling taken from wells at different *** levels were determined by a standard colorimetric method in two seasonal periods,the dry(from April to September)and rainy(from October to March)*** analytical results obtained for physicochemical parameters such as pH,total dissolved solids(TDS),and temperature does not reveal any notable difference between the rainy and dry seasons *** both seasons,the atmospheric temperature average was 22℃.With respect to fluoride content,approximately 50%of the analysed groundwater samples exceeded the limit established by current legislation(1.0 mg/L),obtaining concentration levels in the range of 0.01-2.80 mg/*** study demonstrates the usefulness of the univariate statistical method(quartiles calculation,interquartile range IQR),multivariate principal component analysis(PCA),and cluster analysis to establish a better understanding of the state of the contamination of the waters in the region studied.

关键词： Source water protection Santiago del Estero Multivariate statistical analysis Fluoride Spectrophotometry

O-(β-hydroxyethyl)rutosides determination by micellar flow injection(FI)-spectrofluorimetry

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Journal of Pharmaceutical analysis 2014年第6期4卷 368-373页

作者： Cecilia Mariana Peralta Liliana Patricia Fernndez Instituto de químrica de San Luis (INquISAL-CONICET) 5700 San Luis Argentina rea de qui mica Fisica Facultacl de QuímicaBioquímica y Farmacia Chacabuco y PedemeraUniversidaci Nacional de San Luis 5700 San Luis Argentina reci de qufmica analítica Facultacl de Química Bioquímica y Farmacia Chacabuco y PedemeraUniversidad Nacional de San Luis 5700 San Luis Argentina

A simple,*** and economic flow injection spectrofluorimetric method was developed for the determination of O-（β-hydroxyethyl）*** procedure was based on the use of an anionic surfactant such as sodium dodecyl sulfate to provide an appreciable O-（β-hydroxyethyl）rutosides fluorescence enhancement,increasing considerably the sensitivity of *** the variables affecting the fluorescence intensity were studied and *** flow rate was 5 mL/min with detection at 450 nm（after excitation at 346 nm）.A linear correlation between drug amount and peak area was established for 0-（β-hydroxyethyl）rulosides in the range of 0.01-200 μg/mL with a detection limit of0.001 μg/mL（s/n = 3）.Validation processes were performed by recovering studies with satisfactory *** new methodology can be employed for the routine analysis of 0-（P-hydroxyethyl）rutosides in bulks as well as in commercial formulations.

关键词： O-(β-hydroxyethyl)rutosides Micellar enhancement Flow injection Spectrofluorimetry Pharmaceuticals

determination of L-norvaline and L-tryptophan in dietary supplements by nano-LC using an O-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11- dihydroquinidine-silica hybrid monolithic column

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Journal of Pharmaceutical analysis 2020年第1期10卷 70-77页

作者： Dongsheng Xu Elena Sanchez-Lopez Qiqin Wang Zhengjin Jiang María Luisa Marina departamento de química analítica Química Física e Ingeniería QuímicaUniversidad de AlcalaCtra.Madrid-Barcelona Km.33.60028871Alcala de Henares(Madrid)Spain Institute of Pharmaceutical analysis College of PharmacyJinan UniversityGuangzhou510632China department of Pharmacy and Guangdong Province Key laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine&New Drug Research Jinan UniversityGuangzhou510632China Instituto de Investigacion química“Andres M.del Río”(IQAR) Universidad de AlcalaCtra.Madrid-Barcelona Km.33.60028871Alcala de Henares(Madrid)Spain

An analytical methodology based on an O-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11-dihydroquinidine(MQD)-silica hybrid monolithic column was developed for the enantioseparation of 9-fluorenylmethoxycarbonyl(FMOC)derivatized amino acids by nano-liquid *** mobile phase was optimized including the apparent pH,content of ACN,and concentration of the buffer to obtain a satisfactory enantioresolution performance.27 FMOC derivatized amino acids including 19 protein and 8 non-protein amino acids were tested,and 19 out of them were enantiomerically discriminated obtaining baseline separation for 11 of *** characteristics of the method were evaluated for norvaline and tryptophan in terms of linearity,precision,accuracy,limits of detection(LOD)and quantitation(LOQ)showing good performance to be applied to the enantiomeric determination of these amino acids in dietary *** and LOQ values were 9.3 and 31 mM for norvaline enantiomers and 7.5 and 25 mM for tryptophan enantiomers,*** contents of D-norvaline and D-tryptophan were below their respective LODs in all the analyzed *** of L-tryptophan and L-norvaline showed good agreement with the labeled contents except for one sample which did not show presence of L-norvaline,contrary to the label indication.

关键词： 9-Fluorenylmethoxycarbonyl Amino acids Chiral separation Nano-LC quinidine-silica hybrid monolithic column

Carbon nanodots:a new precursor to achieve reactive nanoporous HOPG surfaces

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Nano Research 2020年第12期13卷 3425-3432页

作者： Cristina Gutiérrez-Sánchez Emiliano Martínez-Periñán Carlos Busó-Rogero Mónica Revenga-Parra Félix Pariente Encarnación Lorenzo departamento de química analítica y Análisis Instrumental Universidad Autónoma de MadridCampus de CantoblancoMadrid28049Spain Institute for Advanced Research in Chemical Sciences(IAdChem) Universidad Autónoma de MadridCampus de CantoblancoMadrid28049Spain IMdeA-Nanoscience.Faraday 9 Campus Cantoblanco-UAMMadrid28049Spain

In the present work we develop an electrochemical assisted method to form nanopores on the surface of highly oriented pyrolytic graphite(HOPG),which was accomplished by a simple electrochemical route and a scalable nanomaterial,carbon nanodots,without applying high voltages,high temperatures or toxic *** electrodes are in a solution of N-enrich carbon nanodots in acidic media and the potential scans applied on HOPG lead to the formation of a spatially inhomogeneous porous *** diameter of the resulting nanopores can be tuned by controlling the number of electrochemical reduction *** resulting nanoporous surfaces are characterized by atomic force microscopy,Raman spectroscopy,scanning electrochemical microscopy,electrochemical impedance spectroscopy and *** nanoporous HOPG showed high *** the potential of these surfaces to the development of energy storage devices is demonstrated.

关键词： nanoporous highly oriented pyrolytic graphite(HOPG) carbon nanodots supercapacitor

Antioxidant Capacity in Vanilla Extracts Obtained by Applying Focused Microwaves

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Food and Nutrition Sciences 2013年第8期4卷 244-253页

作者： Adalith Rojas-López María P.Canizares-Macías departamento de química analítica Facultad de QuímicaUniversidad Nacional Autonoma de MexicoMexico D.F.Mexico

ORAC method and a continuous flow injection method based on Folin-Ciocalteau reaction (FI-FC) were used for determining the antioxidant activity in extracts obtained by using focused microwaves. analysis of the antioxidant capacity (AC) of the main compounds of vanilla (vanillin, p-hydroxybenzaldehyde, p-hydroxybenzoic acid and vanillic acid) was also carried out. Vanilla extracts obtained by using focused microwaves had a higher AC (between 72% and 117%) than the obtained by conventional methods. Vanillin had a linear correlation with the antioxidant capacity of the extracts and it is the most influential compound in the antioxidant power. The AC calculated by the ORAC method and the FI-FC method had a ratio 2:1 because of different kinetics and reaction mechanisms of the antioxidants with the reagents, so it is necessary more than one method to establish the antioxidant power in food. On base on the results of the present study microwaves energy can be used to obtain vanilla extracts to improve the AC of them.

关键词： Focused Microwaves Vanilla Antioxidant Capacity ORAC Method Flow Injection Folin-Ciocalteau

HS-SPME/GC-MS analysis of VOC and Multivariate Techniques Applied to the Discrimination of Brazilian Varieties of Mango

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American Journal of analytical Chemistry 2014年第3期5卷 157-164页

作者： Clícia Maria de Jesus Benevides Marcos de Almeida Bezerra Pedro Afonso P. Pereira Jailson Bittencourt de Andrade departamento de Ciências da Vida Universidade do Estado da Bahia (UNEB) Salvador Brazil Instituto de química Universidade Federal da Bahia (UFBA) Salvador Brazil laboratório de química analítica Universidade Estadual do Sudoeste da Bahia (UESC) Jequié Brazil

The present study analyzed the volatile compounds of three mango varieties (Tommy Atkins, Rosa and Espada) using the static headspace technique with SPME coupled to CG-MS. Multivariate methodologies, such as factorial design and response surface methodology, were used to optimize the conditions of adsorption and desorption of these substances. The data were evaluated by using principal components analysis (PCA) and hierarchical grouping analysis, in order to visualize grouping tendencies of volatile compounds. Thirty-seven volatile compounds belonging to different chemical classes, such as esters, terpenes, alcohols and others, were tentatively identified in the three varieties of mango. Amongst them, twenty-three presented chromatographic peaks with relative areas larger than 2%. The multivariate analysis made it possible to visualize the grouping tendencies of the mango samples, according to the presence of their respective volatile substances, and enabled the identification of the groups of substances responsible for the discrimination among the three varieties.

关键词： Mango Volatiles Multivariate Techniques HS-SPME/GC-MS Chemometrics

determination of drug,excipients and coating distribution in pharmaceutical tablets using NIR-CI

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Journal of Pharmaceutical analysis 2012年第2期2卷 90-97页

作者： Anna Palou Jordi Cruz Marcelo Blanco Jaume Tomàs Joaquín de los Ríos Manel Alcalà Unitat de química analítica Departament de QuímicaFacultat de CiènciesUniversitat Autònoma de Barcelona08193 BellaterraBarcelonaSpain Escola Universitària Salessiana de Sarrià Passeig Sant Joan Bosco7408017 BarcelonaSpain Esteve Farma c/Sant Martí s/n08197 MartorellesBarcelonaSpain

The growing interest of the pharmaceutical industry in Near Infrared-Chemical Imaging (NIR-CI) is a result of its high usefulness for quality control analyses of drugs throughout their production process (particularly of its non-destructive nature and expeditious data acquisition).In this work,the concentration and distribution of the major and minor components of pharmaceutical tablets are determined and the spatial distribution from the internal and external sides has been *** addition,the same NIR-CI allowed the coating thickness and its surface distribution to be *** were processed to extract the target data and calibration models constructed using the Partial Least Squares (PLS) *** concentrations of Active Pharmaceutical Ingredient (API) and excipients obtained for uncoated cores were essentially identical to the nominal values of the pharmaceutical *** the predictive ability of the calibration models applied to the coated tablets decreased as the coating thickness increased.

关键词： Near infrared Chemical Imaging (NIR-CI) Hyperspectral imaging Component distribution Tablet coating distribution Partial Least Squares (PLS) regression