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Ventricular repolarization markers for predicting malignant arrhythmias in clinical practice

World Journal of Clinical Cases 2015年第8期3卷 705-720页

作者： Yaniel Castro-torres Raimundo Carmona-Puerta Richard E Katholi Facultad de Medicina Universidad de Ciencias Médicas Dr.Serafín Ruiz de Zárate Ruiz Cardiocentro Ernesto Che Guevara Southern Illinois University School of Medicine and Prairie Cardiovascular Consultants

Malignant cardiac arrhythmias which result in sudden cardiac death may be present in individuals apparently healthy or be associated with other medical conditions. The way to predict their appearance represents a challenge for the medical community due to the tragic outcomes in most cases. In the last two decades some ventricular repolarization(VR) markers have been found to be useful to predict malignant cardiac arrhythmias in several clinical conditions. The corrected QT, QT dispersion, Tpeak-Tend, Tpeak-Tend dispersion and Tp-e/QT have been studied and implemented in clinical practice for this purpose. These markers are obtained from 12 lead surface electrocardiogram. In this review we discuss how these markers have demonstrated to be effective to predict malignant arrhythmias in medical conditions such as long and short QT syndromes, Brugada syndrome, early repolarization syndrome, acute myocardial ischemia, heart failure, hypertension, diabetes mellitus, obesity and highly trained athletes. Also the main pathophysiological mechanisms that explain the arrhythmogenic predisposition in these diseases and the basis for the VR markers are discussed. However, the same results have not been found in all conditions. Further studies are needed to reach a global consensus in order to incorporate these VR parameters in risk stratification of these patients.

关键词： Electrocardiographic predictor Ventricular repolarization markers Ventricular fibrillation Sudden cardiac death QT interval Corrected QT interval QT dispersion Tpeak-Tend interval Tpeak-Tend QT ratio

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Fetal vs adult mesenchymal stem cells achieve greater gene expression, but less osteoinduction

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World Journal of Stem Cells 2015年第1期7卷 223-234页

作者： Juan E Santiago-torres Rebecca Lovasz Alicia L Bertone Comparative Orthopedic Research Laboratory Department of Veterinary Clinical Sciences College of Veterinary Medicine The Ohio State University Columbus OH 43210 United States College of Medicine The Ohio State University Columbus OH 43210 United States

AIM: To investigate adenoviral transduction in mesenchymal stem cells(MSCs) and effects on stemness in vitro and function as a cell therapy in ***: Bone marrow-derived adult and fetal MSC were isolated from an equine source and expanded in monolayer tissue culture. Polyethylenimine(PEI)-mediated transfection of pc DNA3-e GFP or adenoviral transduction of green fluorescent protein(GFP) was evaluated in fetal MSCs. Adenoviral-mediated transduction was chosen for subsequent experiments. All experiments were carried out at least in triplicate unless otherwise noted. Outcome assessment was obtained by flow cytometry or immunohystochemistry and included transduction efficiency, cell viability, stemness(i.e., cell proliferation, osteogenic and chondrogenic cell differentiation), and quantification of GFP expression. Fetal and adult MSCs were then transduced with an adenoviral vector containing the gene for the bone morphogenic protein 2(BMP2). In vitro BMP2 expression was assessed by enzyme linked immunosorbent assay. In addition, MSC-mediated gene delivery of BMP2 was evaluated in vivo in an osteoinduction nude mouse quadriceps model. New bone formation was evaluated by microradiography and ***: PEI provided greater transfection and viability in fetal MSCs than other commercial chemical reagents. Adenoviral transduction efficiency was superior to PEI-mediated transfection of GFP in fetal MSCs(81.3% ± 1.3% vs 35.0% ± 1.6%, P < 0.05) and was similar in adult MSCs(78.1% ± 1.9%). Adenoviral transduction provided significantly greater expression of GFP in fetal than adult MSCs(7.4 ± 0.1 vs 4.4 ± 0.3 millions of mean fluorescence intensity units, P < 0.01) as well as significantly greater in vitro BMP2 expression(0.16 pg/cell-day vs 0.10 pg/cell-day, P < 0.01). Fraction of fetal MSC GFP positive cells decreased significantly faster than adult MSCs(1.15% ± 0.05% vs 11.4% ± 2.1% GFP positive at 2 wk post-transduction, P < 0.05). Cell proliferation and osteo

关键词： Mesenchymal stem cells Biomarkers Next generation sequencing Diagnostic tool Tumor-initiating cells

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Hydrothermal synthesis of pyrrhotite(Fex-1S) nanoplates and their antibacterial, cytotoxic activity study

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Progress in Natural Science:Materials International 2018年第4期28卷 447-455页

作者： Liliana Argueta-Figueroa Nayely torres-Gómez René García-Contreras A.R.Vilchis-Nestor O.Martínez-Alvarez L.S.Acosta-torres M.C.Arenas-Arrocena Laboratorio de Investigación Interdisciplinaria área de Nanoestructuras y Biomateriales Escuela Nacional de Estudios Superiores Unidad León Universidad Nacional Autónoma de México Centro Conjunto de Investigación en Química Sustentable (CCIQS) UEAMex-UNAM Departamento de Ingeniería en Energía Universidad Politécnica de Guanajuato

The aim of this study was to synthesize and characterize Fex-1S 2D-nanostructures with pyrrhotite phase,as well as to explore their biological(antibacterial and cytotoxic)properties,namely the expression of reactive oxygen species(ROS)in the exposure of cells and *** on hydrothermal synthesis,the characterization of asprepared 2D-nanostructures was performed by XRD,SEM,EDS,and TEM,in which the single-crystalline pyrrhotite phased Fex-1S nanoplate morphology was *** antibacterial activities of Fex-1S nanoplates against human pathogenic strains such as Staphylococcus aureus,Escherichia coli,and Enterococcus faecalis were *** inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)were determined following the broth microdilution *** and expression of intracellular ROS of pyrrhotite nanoplates on Human Gingival Fibroblast(HGF),Human Pulp Cells(HPC)and Human Osteoblast(HBC)were *** viability was determined by the MTT *** experiments were performed of three independent experiments and data were analyzed by Kruskal-Wallis and Mann-Whitney tests,also Pearson′s Correlation was *** nanoplates exhibited good bactericidal *** types of cells tested showed slight *** was found that intracellular ROS is produced when cells and bacteria tested are exposed to pyrrhotite nanoplates in presence of both air and peroxide *** production levels were higher in the bacteria than the cells exposed to these nanoplates.

关键词： Hydrothermal synthesis Iron sulfide nanoplates Minimal inhibitory concentration Antibacterial effect Cytotoxicity assay

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In vitro antioxidant,antilipoxygenase and antimicrobial activities of extracts from seven climbing plants belonging to the Bignoniaceae

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Journal of Integrative Medicine 2018年第4期16卷 255-262页

作者： Carola Analla torres Cristina Marisel Perez Zamora Maria Beatriz Nunez Ana Maria Gonzalez Laboratory of Microbiology and Pharmaceutical Technology Department of Basic and Applied SciencesNational University of Chaco AustralPresidencia Roque Saenz Pena 3700ChacoArgentina National Council for Scientific and Technical Research(CONICET) Godoy Cruz 2290Buenos Aires C1425FQBArgentina Institute of Botany of the Northeast(IBONE-CONICET) Sargento Juan Bautista Cabral 2131CorrientesArgentina

Objectives： This study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalyrnrna rnarginatum （Cham.） DC., Amphilophium vauthieri DC., Cuspidaria convoluta （VEIL） A. H. Gentry, Dolichandra dentata （K. Schum.） L. G. Lohmann, Fridericia caudigera （S. Moore） L. G. Lohmann, Fridericia chica （Bonpl.） L. G. Lohmann and Tanaecium selloi （Spreng.） L. G. Lohmann. Methods： The antioxidant activity was evaluated using three methods, 2,2＇-azino-bis（3-ethylbenzothiazo line-6-sulfonic acid）（ABTS）, 2,2-diphenyl-l-picrylhydrazyl （DPPH）, and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration （MIC） and minimal bactericidal]fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry. Results： C convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS~ radicals and reducing Fe3＋ ion. These extracts showed a notable inhibition of lipnxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C convoluta had higher total phenol content, better antioxidant activity and superior anti- inflammatory and antimicrobial activity. The main phenolic compounds found in this extract

关键词： Cuspidaria Fridericia Antioxidants Lipoxygenase Antimicrobials Herbal drugs Free radical scavengers

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Integrity and resilience in the face of multiple crises:commentary from Puerto Rico

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Forensic Sciences Research 2021年第3期6卷 316-319页

作者： Richard J.Noel Jr Jose A.torres-Ruiz Department of Basic Sciences School of MedicinePonce Health Sciences UniversityPoncePRUSA Office of the Chancellor Ponce Health Sciences UniversityPoncePRUSA

Since 2010,the population of Puerto Rico has declined by 11.8%and is currently 3.3 million peo-ple[1].This worrisome trend is a result of a pleth-ora of island-wide challenges spanning financial difficulties,natural disasters,and *** over a decade of economic hardship and debt,incapacitating hurricanes,Irma and Maria,destroyed large swaths of the island in *** still recovering from that disaster,a magnitude 6.4 earthquake centered about 5 miles off the south-western coast on January 7,2020,destroying build-ings and roads in southwestern Puerto *** event,and subsequent aftershocks that continue until today,further aggravate an already stressed *** the mix,viral epidemics have brought fur-ther economic,social,and health-related *** Rico was the centre of the 2016-2017 Zika virus infections,representing over 85%of the US infections in 2016[2].

关键词： island disaster southwestern

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A Hybrid Statistical-Dynamical Downscaling of Air Temperature over Scandinavia Using the WRF Model

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Advances in Atmospheric Sciences 2020年第1期37卷 57-74页

作者： Jianfeng WANG Ricardo M.FONSECA Kendall RUTLEDGE Javier MARTÍN-torres Jun YU Department of Mathematics and Mathematical Statistics UmeåUniversitySE 90187UmeåSweden Group of Atmospheric Science Division of Space TechnologyDepartment of Computer ScienceElectrical and Space EngineeringLuleåUniversity of TechnologySE 97187 LuleåSweden Novia University of Applied Sciences PO BOX 6FI-65201 VaasaFinland Instituto Andaluz de Ciencias de la Tierra 18100 GranadaSpain The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry Institute for Planetary MaterialsOkayama University at MisasaTottori 682-0193Japan

An accurate simulation of air temperature at local scales is crucial for the vast majority of weather and climate *** this work,a hybrid statistical–dynamical downscaling method and a high-resolution dynamical-only downscaling method are applied to daily mean,minimum and maximum air temperatures to investigate the quality of localscale estimates produced by *** two downscaling approaches are evaluated using station observation data obtained from the Finnish Meteorological Institute over a near-coastal region of western *** dynamical downscaling is performed with the Weather Research and Forecasting(WRF)model,and the statistical downscaling method implemented is the Cumulative Distribution Function-transform(CDF-t).The CDF-t is trained using 20 years of WRF-downscaled Climate Forecast System Reanalysis data over the region at a 3-km spatial resolution for the central month of each *** performance of the two methods is assessed qualitatively,by inspection of quantile-quantile plots,and quantitatively,through the Cramer-von Mises,mean absolute error,and root-mean-square error *** hybrid approach is found to provide significantly more skillful forecasts of the observed daily mean and maximum air temperatures than those of the dynamical-only downscaling(for all seasons).The hybrid method proves to be less computationally expensive,and also to give more skillful temperature forecasts(at least for the Finnish near-coastal region).

关键词： WRF air temperature Cumulative Distribution Function-transform hybrid statistical–dynamical downscaling,model evaluation Scandinavian Peninsula

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A lattice Boltzmann exploration of two-phase displacement in 2D porous media under various pressure boundary conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1782-1798页

作者： Guanxi Yan Zi Li Thierry Bore Sergio Andres Galindo torres Alexander Scheuermann Ling Li School of Civil Engineering University of QueenslandSt LuciaBrisbaneQLD4072Australia School of Engineering Westlake UniversityHangzhou310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou310024China

While experimental designs developed in recent decades have contributed to research on dynamic nonequilibrium effects in transient two-phase flow in porous media,this problem has been seldom investigated using direct numerical simulation(DNS).Only a few studies have sought to numerically solve Navier—Stokes equations with level-set(LS)or volume-of-fluid(VoF)methods,each of which has constraints in terms of meniscus dynamics for various flow velocities in the control volume(CV)*** Shan—Chen multiphase multicomponent lattice Boltzmann method(SC-LBM)has a fundamental mechanism to separate immiscible fluid phases in the density domain without these ***,this study applied it to explore two-phase displacement in a single representative elementary volume(REV)of two-dimensional(2D)porous *** a continuation of a previous investigation into one-step inflow/outflow in 2D porous media,this work seeks to identify dynamic nonequilibrium effects on capillary pressure—saturation relationship(P_(c)—S)for quasi-steady-state flow and multistep inflow/outflow under various pressure boundary *** simulation outcomes show that P_(c),S and specific interfacial area(a_(nw))had multistep-wise dynamic effects corresponding to the multistep-wise pressure boundary *** finer adjustments to the increase in pressure over more steps,dynamic nonequilibrium effects were significantly alleviated and even finally disappeared to achieve quasisteady-state inflow/outflow ***,triangular wave-formed pressure boundary conditions were applied in different periods to investigate dynamic nonequilibrium effects for hysteretical Pc—*** results showed overshoot and undershoot of P_(c)to S in loops of the nonequilibrium *** addition,the flow regimes of multistep-wise dynamic effects were analyzed in terms of Reynolds and capillary numbers(Re and Ca).The analysis of REV-scale flow regimes showed higher Re(1

关键词： Two-phase flow Porous media Dynamic effects Multistep in/outflow Capillary pressure Interfacial area Flow regimes

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Lid scrubbing with a gel combining natural extracts for dry eye treatment

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International Journal of Ophthalmology(English edition) 2023年第7期16卷 1053-1059页

作者： Blanca Diaz-Vega Carlos Rodriguez-Fabuel Sofia Vitores-Mate Carlos Carpena-torres Gran Visión Oftalmología Madrid 28026Spain e-Health Vision Department of OphthalmologyMadrid 28232Spain Gran Óptica Madrid Department of Dry EyeMadrid 28026Spain Ocupharm Research Group Department of Optometry and VisionFaculty of Optics and OptometryComplutense University of MadridMadrid 28037Spain

AIM:To evaluate the effect of lid scrubbing using a gel combining different natural extracts on ocular signs and symptoms of dry eye ***:A retrospective study was performed on 19 dry eye patients(51.1±16.0y).Non-invasive tear break-up time,tear meniscus height,meibomian gland loss,lipid layer thickness,conjunctival redness,corneal staining,ocular surface disease index(OSDI),and ocular pain intensity were measured before(baseline),1wk,and 2mo after lid scrubbing with a gel containing different natural extracts(okra extract,aloe vera leaf juice,hydrolysed soy protein,caffeine,citrus unshiu peel extract,and raspberry seed oil).RESULTS:Compared with the baseline,there was a statistically significant improvement in both first(P=0.048)and average(P=0.026)non-invasive tear break-up time 2mo after treatment,as well as in corneal staining(P=0.043,0.012),OSDI(P<0.001),and ocular pain intensity(P<0.001)after 1wk and *** addition,there was no correlation between ocular signs and ***:The lid scrubbing with a gel combining different natural extracts show beneficial effects on tear film stability,corneal damage,and ocular symptoms,which is the reason why this therapeutic procedure is proposed as an alternative for dry eye ***,it is not possible to attribute this beneficial effect solely to the presence of the natural extracts in the gel,primarily due to the absence of a negative control group.

关键词： lid hygiene natural extracts okra aloe vera soy dry eye

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Green extraction of phenolic compounds from Perle Hallertau and Nuggets hop pellets

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Food Bioscience 2022年第6期50卷 474-481页

作者： Vanesa Sanz Maria Dolores torres Jose M.Lopez Vilarino Herminia Dominguez Chemical Engineering Department Faculty of ScienceCampus OurenseUniversity of VigoSpain R&D Department Hijos de RiveraS.A.U.c/ José Maria Riveranº6A CoruñaSpain

Operation conditions to recover and quantify active compounds from Perle Hallertau (PH) and Nuggets (N) hops, following a sequential combination of ultrasound and microwave assisted ethanolic extraction were studied. Ultrasound treatment (55 °C, 60% ethanol, 30 minutes) allowed extracts with phenolic contents of 160.43 mg GAE/g extract and ABTS radical scavenging capacity equivalent to 400.24 mg Trolox/g extract for PH. Optimal conditions for N were found at 55 °C, using 60% ethanol for 120 minutes (98.80 mg GAE/g extract) and 55 °C, 40% ethanol for 180 min (370.00 mg Trolox/g extract). The remaining solids were further processed under ethanolic microwave extraction (130–190 °C, 5 minutes) with the optimal results obtained at 190 °C for PH (77.11 and 98.67 mg GAE/g extract) and N (226.96 and 368.72 mg Trolox/g extract). Results obtained provided hops pellets as a rich source of active compounds that could be suitable for food and no food industry applications.

关键词： Humulus lupulus Cascade extraction Environmentally friendly technologies Ultrasound Microwave Antioxidants

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Conical tank level control using fractional order PID controllers： a simulated and experimental study

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Control Theory and Technology 2016年第4期14卷 369-384页

作者： Cristian JAUREGUI Manuel A. DUARTE-MERMOUD Rodrigo OROSTICA Juan Carlos TRAVIESO-torres Orlando BEYTIA Electrical Engineering Department and Advanced Mining Technology Center Universidad de Chile Av. Tupper 2007 Casilla 412-3 Santiago Chile Industrial Technologies Department Technological Faculty Universidad de Santiago de Chile Av. El Belloto 3735 Santiago Chile

In this paper, simulated and experimental results on the conical tank level control are presented. PI/PID controllers of integer order （IO） as well as of fractional order （FO） are studied and compared. The tuning parameters are obtained first by using root locus （RL） and Ziegler and Nichols methods, for comparison purposes. Next, particle swarm optimization （PSO） is employed to determine the optimal controllers＇ parameters using as fitness function the integral of the absolute value of tracking error （IAE）. From the experimental results it is concluded that PI/FOPI are the controllers presenting the lowest IAE indexes, whereas PID/FOPID controllers present the lowest energy consumption by the control signal.

关键词： Level control conical tank PID control fractional PID control experimental control

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