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Aminoguanidine impedes human pancreatic tumor growth and metastasis development in nude mice

World Journal of Gastroenterology 2009年第9期15卷 1065-1071页

作者： nora A Mohamad Graciela P Cricco Lorena A Sambuco Máximo Croci Vanina A Medina Alicia S Gutiérrez Rosa M Bergoc Elena S Rivera Gabriela A Martín Laboratory of Radioisotopes School of Pharmacy and BiochemistryUniversity of Buenos AiresJunín 954 (C1113AAB)Buenos AiresArgentina Institute of Immunooncology Dr. Ernesto Crescenti Av. Córdoba 3200 (C1187AAS)Buenos AiresArgentina National Research Council (CONICET) Av. Rivadavia 1917 (C1033AAJ)Buenos AiresArgentina

AIM:To study the action of aminoguanidine on pancreatic cancer xenografts in relation to cell proliferation,apoptosis,redox status and ***:Xenografts of PANC-1 cells were developed in nude mice. The animals were separated into two groups:control and aminoguanidine treated. Tumor growth,survival and appearance of metastases were determined in vivo in both groups. Tumors were excised and ex vivo histochemical studies were performed. Cell growth was assessed by Ki-67 expression. Apoptosis was studied by intratumoral expression of B cell lymphoma-2 protein (Bcl-2) family proteins and Terminal deoxynucleotidyl transferase biotin-dUTP Nick End Labeling (Tunel). Redox status was evaluated by the expression of endothelial nitric oxide synthase (eNOS),catalase,copper-zinc superoxide dismutase (CuZnSOD),manganese superoxide dismutase (MnSOD) and glutathione peroxidase (GPx). Finally,vascularization was determined by Massons trichromic staining,and by VEGF and CD34 ***:Tumor volumes after 32 d of treatment by aminoguanidine (AG) were significantly lower than in control mice (P < 0.01). Median survival of AG mice was significantly greater than control animals (P < 0.01). The appearance of both homolateral and contralateral palpable metastases was significantly delayed in AG group. Apoptotic cells,intratumoral vascularization (trichromic stain) and the expression of Ki-67,Bax,eNOS,CD34,VEGF,catalase,CuZnSOD and MnSOD were diminished in AG treated mice (P < 0.01),while the expression of Bcl-2 and GPx did not ***:The antitumoral action of aminoguanidine is associated with decreased cell proliferation,reduced angiogenesis,and reduced expression of antioxidant enzymes.

关键词： Aminoguanidine Pancreatic ductal carcinoma Tumor growth Metastasis Apoptosis

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Radiative transition

Radiative transition

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作者： nora Brambilla Antonio Vairo

＜正＞4.2.1 Introduction Radiative transitions historically have played important roles in establishing new quarkonium *** today,these simple processes are still of considerable exper- imental and theoretical *** the theoretical side,the photon serves as a clean probe to internal structrue of quarkonium,therefore a thorough understanding of these

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Fluorometric Viability Assessment of Capacitated and Acrosome-Reacted Boar Spermatozoa by Flow Cytometry

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Optics and Photonics Journal 2013年第1期3卷 40-44页

作者： Reyna fierro Humberto Gonzalez-Marquez Rocio Ortiz Jerome Chevrier Bernard Foliguet Departamento de Ciencias de la Salud Universidad Autonoma Metropolitana-IztapalapaMexico CityMexico Laboratoire d’Histologie Embryologie et Microscopie ElectroniqueUniversite LorraineNancyFrance

Sperm capacitation involves functional changes, such as the removal or appearance of specific molecules and changes in the plasma membrane;the acrosome reaction (AR) is an exocytotic event induced by calcium influx, enabling the spermatozoa to penetrate the zona pellucida. These processes can be achieved only if the spermatozoa have good viability;indeed, determination of sperm viability is used for the assessment of semen quality. Membrane integrity and mitochondrial activity are important viability parameters of spermatozoa and fluorescent techniques based on membrane permeability to dyes have been developed to determine these parameters. The aim of this work was to determine the viability of boar sperm (fresh, one hour of capacitation induction and 20 min of AR induction) by flow cytometry using propidium iodide (PI) (1.25 μg/mL) and rhodamine 123 (R123) (0.20 μg/mL). Aliquots of 5 × 105 sperm were incubated with each fluorochrome separately and simultaneously for 10 or 20 min, respectively, at 38℃. The proportion of labeled spermatozoa and their fluorescence intensities were measured using a flow cytometer. The fluorescence index (FI) with PI gradually increased during the incubation and we found significant differences between all the groups. With R123, the FI increased in the capacitated sperm but decreased in the acrosome-reacted sperm, with significant differences between the fresh and capacitated spermatozoa. Our results suggest that the increase in the R123 fluorescence intensity in capacitated spermatozoa is due to changes in the mitochondrial membrane activity because the spermatozoa experienced changes in membrane fluidity and flagellar activation during capacitation. The use of fluorochromes and flow cytometry is a good tool for monitoring many markers of sperm function. Although capacitation and AR processes have been well studied, there is still much information to be elucidated with regard to these complex processes.

关键词： Boar Sperm Flow Cytometry Propidium Iodide Rhodamine 123 Viability

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Robust Deep Learning Model for Black Fungus Detection Based on Gabor Filter and Transfer Learning

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Computer Systems Science & Engineering 2023年第11期47卷 1507-1525页

作者： Esraa Hassan Fatma M.Talaat Samah Adel Samir Abdelrazek Ahsan Aziz Yunyoung Nam nora El-Rashidy Machine Learning and Information Retrieval Department Faculty of Artificial IntelligenceKafrelsheikh UniversityKafrelsheikhEgypt Electronics and Communication Engineering Department Faculty of Engineering Horus UniversityDamiettaEgypt Information Systems Department Faculty of Computers and InformationMansoura UniversityMansoura35516Egypt Department of ICT Convergence Soonchunhyang UniversityAsanKorea

Black fungus is a rare and dangerous mycology that usually affects the brain and lungs and could be life-threatening in diabetic ***,some COVID-19 survivors,especially those with co-morbid diseases,have been susceptible to black ***,recovered COVID-19 patients should seek medical support when they notice mucormycosis *** paper proposes a novel ensemble deep-learning model that includes three pre-trained models:reset(50),VGG(19),and *** approach is medically intuitive and efficient compared to the traditional deep learning *** image dataset was aggregated from various resources and divided into two classes:a black fungus class and a skin infection *** the best of our knowledge,our study is the first that is concerned with building black fungus detection models based on deep learning *** proposed approach can significantly improve the performance of the classification task and increase the generalization ability of such a binary classification *** to the reported results,it has empirically achieved a sensitivity value of 0.9907,a specificity value of 0.9938,a precision value of 0.9938,and a negative predictive value of 0.9907.

关键词： Black fungus COVID-19 Transfer learning pre-trained models medical image

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Stroke in COVID-19: a single-centre initial experience in a hotspot of the pandemic

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Stroke & Vascular Neurology 2020年第4期5卷 331-336页

作者： Ivo Bach Pratibha Surathi nora Montealegre Osama Abu-Hadid Sara Rubenstein Sviatoslav Redko Siddharth Gupta Machteld Hillen Pratit Patel Priyank Khandelwal Adham Kamel Department of Neurology and Neurosciences New Jersey Medical SchoolNewarkNew JerseyUSA Department of Neurological Surgery New Jersey Medical SchoolNewarkNew JerseyUSA

Background COVID-19,caused by SARS-CoV-2,is a global pandemic that has been an immense burden on healthcare systems all over the *** patients may be at higher risk for acute ischaemic stroke(AIS).We present our experience with AIS in patients with *** We reviewed all patients admitted to our hospital during a 6-week period with a positive nasopharyngeal swab test for *** these patients,we identified *** reviewed the demographics,clinical,laboratory,imaging characteristics,treatments received and outcomes of AIS in patients with *** We identified 683 patients admitted with COVID-19 during the study period,of which 20 patients had ***-vessel occlusion(LVO)was noted in 11 patients(55%).Intravenous alteplase was administered in four patients(20%)and mechanical thrombectomy was performed in five patients(25%).Respiratory symptoms preceded the onset of AIS in most of the patients(70%)by 1 to 21 *** in patients with AIS was 50%compared with 26%of all COVID-19 *** of these patients died due to non-neurological causes(70%).Three patients with AIS had clinical and imaging findings consistent with COVID-19,but were negative for multiple nasopharyngeal swab *** LVO was more common in patients with AIS and *** had more severe disease and higher mortality *** of the patients had respiratory symptoms preceding AIS by days to *** could explain certain patients with clinical picture of COVID-19 but negative nasopharyngeal swab tests.

关键词： admitted nasopharyngeal acute

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Recovery rates and long-term olfactory dysfunction following COVID-19 infection

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 121-128页

作者： Melanie Dias Zara Shaida nora Haloob Claire Hopkins ENT Department Guy's HospitalLondonUK

Objectives:Olfactory dysfunction is one of the most recognized symptoms of COVID-19,significantly impacting quality of life,particularly in cases where recovery is *** review aims to explore patterns of olfactory recovery post-COVID-19 infection,with particular focus on delayed *** Sources:Published literature in the English language,including senior author's own work,online and social media platforms,and patients'anecdotal ***:A comprehensive review of the literature was undertaken by the authors with guidance from the senior author with expertise in the field of ***:Based on self-report,an estimated 95%of patients recover their olfactory function within 6 months post-COVID-19 ***,psychophysical testing detects higher rates of persistent olfactory *** has been found to continue for at least 2 years postinfection;negative prognostic indicators include severe olfactory loss in the acute phase,female sex,and older *** in quantitative and qualitative disturbance in prolonged cases likely reflects both peripheral and central pathophysiological *** of many of the reviewed studies reflect lack of psychophysical testing and baseline olfactory ***:Post-COVID-19 olfactory dysfunction remains a significant health and psychosocial *** evidence is improving awareness and knowledge among clinicians to better support patients through their olfactory rehabilitation,with hope of recovery after several months or *** research is needed to better understand the underlying pathogenesis of delayed recovery,identify at risk individuals earlier in the disease course,and develop therapeutic targets.

关键词： anosmia COVID-19 olfaction parosmia recovery

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Toxicity and removal of phenanthrene,fluoranthene and pyrene by two Navicula species,***（a commercial species） and ***（a local isolate）

Toxicity and removal of phenanthrene,fluoranthene and pyrene...

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中国藻类学会第八次会员大会暨第十六次学术讨论会

作者： nora Fung-yee Tam Department of Biology and Chemistry City University of Hong KongTat Chee AvenueKowloonHong Kong SARChina

＜正＞The present study showed that the tolerance of two Navicula diatoms,a local isolate {Navicula sp.) and a commercial species {Navicula incerta),to three polycyclic aromatic hydrocarbons（PAHs）,phenanthrene（PHE）,fluoranthene（FLU） and pyrene（PYR）, was PAH- and *** and PYR exhibited comparable median effect concentration（EC50） values（7.39-9.30 mg/L） but were remarkably higher than FLU （0.41-5.16 mg/L）,suggesting that FLU was more toxic to Navicula *** local isolate was more sensitive to FLU toxicity than the commercial species and the EC50 of the local isolate was very low（0.41 mg/L）.Both species were capable to remove PAHs, the efficiency was also PAH-dependent and followed the declining order of PHE＞FLU＞*** the end of 7-days treatment,the biodegradation percentages of PHE,FLU and PYR（calculated based on the difference between the amount of PAH added and the summation of the amount remained in medium,accumulated in cells and abiotic loss） by *** were 65.9%,57.0%and 34.7%,respectively,while their respective values by the local isolate were 74.9%,57.7%and 26.1%.These results indicated that PYR was not only the most difficult PAH to be removed but was also most resistant to biodegradation by these two diatom species than the other two *** removal and biodegradation percentages were affected by the initial concentration of PAHs in the *** FLU and PYR remained in the medium,as well as accumulated in cells,at 5.0 mg/L treatment than at the two lower levels,0.5 and 1.0 mg/L,while the biodegradation percentages of all three PAHs at 5.0 mg/L treatment were also *** only PAH-dependent,the PAH tolerance and removal were also *** local isolate did not exhibit a higher tolerance to PAHs and it did not achieve better removal and biodegradation than the commercial species.

关键词： Biodegradation diatom EC50 microalgae Navicula Polycyclic aromatic hydrocarbons(PAHs)

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Synthesis and Piezoelectric Properties of Pb0.98Sm0.02[(Zry,Ti1–y)0.98(Fe1/23+,Nb1/25+)0.02]O3Ceramics

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Materials Sciences and Applications 2012年第1期3卷 50-58页

作者： Fares Kahoul Louanes Hamzioui nora Abdessalem Ahmed Boutarfaia 不详

The structural and electrical properties of Pb0.98Sm0.02[(Zry,Ti1–y)0.98( Fe1/23+,Nb1/25+)0.02]O3 ceramics system with the composition near the morphotropic phase boundary were investigated as a function of the Zr/Ti ratio by X-ray diffraction (XRD). Studies were performed on the samples prepared by solid state reaction for y = 0.47, 0.49, 051, 0.53, 0.55 and 0.57. Combined with piezoelectric properties results, it was consistently shown that an MPB exists between y = 0.51 and y = 0.55 in this system. When y 0.55, the rhombohedral phase dominates. Lattice parameters of the tetragonal phase and rhombohedral phase were found to vary with chemical composition. The average particle size ranged from 17.18 to 26.05 nm. The dielectric (ε = 1076), tan δ = 0.013 and piezoelectric properties (d31 = 122 pC/N, kp = 0.631 and Qm = 462) obtained were maximum at y = 0.55 which could be suitable for possible electromechanical and energy harvesting applications.

关键词： X-Ray Methods Co-Existence of Phase Piezoelectric Properties Dielectric Properties

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Post-Translational Derepression of Invertase Activity in Source Leaves via Down-Regulation of Invertase Inhibitor Expression Is Part of the Plant Defense Response

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Molecular Plant 2010年第6期3卷 1037-1048页

作者： Katharina B. Bonfig Andrea Gabler Uwe K. Simon nora Luschin-Ebengreuth Martina Hatz Susanne Berger Naseem Muhammad Jurgen Zeier Alok K. Sinha Thomas Roitsch Julius-von-Sachs-Institut fuer Biowissenschaften Lehrstuhl for Pharmazeutische Biologie Universitaet Wuerzburg Julius-von-Sachs-Platz 2 97082 Wuerzburg Germany Institute of Plant Sciences Department of Plant Physiology University of Graz 8010 Graz Austria Zentrum for rnedizinische Grundlagenforschung (ZMF) Medizinische Universitat Graz Stiftingtalstraβe 24 A-8010 Graz Department of Biology Plant Biology Section University of Fribourg Route Albert Gockel 3 CH-1700 Fribourg Switzerland National Institute for Plant Genome Research Aruna Asaf Ali Road New Delhi 110067 India

There is increasing evidence that pathogens do not only elicit direct defense responses, but also cause pronounced changes in primary carbohydrate metabolism. Cell-wall-bound invertases belong to the key regulators of carbohydrate partitioning and source-sink relations. Whereas studies have focused so far only on the transcriptional induction of invertase genes in response to pathogen infection, the role of post-translational regulation of invertase activity has been neglected and was the focus of the present study. Expression analyses revealed that the high mRNA level of one out of three proteinaceous invertase inhibitors in source leaves of Arabidopsis thaliana is strongly repressed upon infection by a virulent strain of Pseudomonas syringae pv. tomato DC3000. This repression is paralleled by a decrease in invertase inhibitor activity. The physiological role of this regulatory mechanism is revealed by the finding that in situ invertase activity was detectable only upon infection by P. syringae. In contrast, a high invertase activity could be measured in vitro in crude and cell wall extracts prepared from both infected and non-infected leaves. The discrepancy between the in situ and in vitro invertase activity of control leaves and the high in situ invertase activity in infected leaves can be explained by the pathogen-dependent repression of invertase inhibitor expression and a concomitant reduction in invertase inhibitor activity. The functional importance of the release of invertase from post-translational inhibition for the defense response was substantiated by the application of the competitive chemical invertase inhibitor acarbose. Posttranslational inhibition of extracellular invertase activity by infiltration of acarbose in leaves was shown to increase the susceptibility to P. syringae. The impact of invertase inhibition on spatial and temporal dynamics of the repression of photosynthesis and promotion of bacterial growth during pathogen infection supports a

关键词： Acarbose Arabidopsis defense responses invertase inhibitor protein invertase plant-microbe interactions Pseudomonas syringae.

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Predictive Study of Velocimetry in the Coronary Artery after Iodinated Contrast Agent Injection

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2017年第1期6卷 93-104页

作者： nora Hocine Julie Colnot Helene Masset Didier Franck Institut de Radioprotection et de Surete Nucleaire(IRSN) Fontenay-aux-RosesFrance Centre Hospitalier Universitaire Henri Mondor CreteilFrance

This study aims to determine the retention time of iodinated contrast agents (ICA) in the coronary artery. The mechanical aspect of ICA displacement was studied in order to better understand the effect of these products on the inner wall of the artery of patients with coronary artery stenosis, undergoing repeated imaging examinations with iodinated contrast agents. ICA flow, ICA and blood flow in the artery were modelled. The fluid was regarded to be viscous, incompressible and Newtonian. Blood flow was presumed to be unidirectional, laminar and unstationary. Iodine flow velocity and retention time were calculated using the Runge-Kutta 4th order method programmed in C++ and MatLab R2013a language. The results showed that for coronary artery CT-scans, ICA retention time is 1 minute 40 seconds and for coronary arteriography it is between 2.41 and 3.61 seconds. The values calculated were compared to theoretical values and to clinical observations. The results enabled us to validate our model.

关键词： Coronary Artery Iodinated Contrast Agent Blood Flow

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