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1.
Phys Rev Lett ; 124(19): 195002, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32469565

RESUMO

The structure of the edge plasma in a magnetic confinement system has a strong impact on the overall plasma performance. We uncover for the first time a magnetic-field-direction dependent density shelf, i.e., local flattening of the density radial profile near the magnetic separatrix, in high confinement plasmas with low edge collisionality in the DIII-D tokamak. The density shelf is correlated with a doubly peaked density profile near the divertor target plate, which tends to occur for operation with the ion B×∇B drift direction away from the X-point, as currently employed for DIII-D advanced tokamak scenarios. This double-peaked divertor plasma profile is connected via the E×B drifts, arising from a strong radial electric field induced by the radial electron temperature gradient near the divertor target. The drifts lead to the reversal of the poloidal flow above the divertor target, resulting in the formation of the density shelf. The edge density shelf can be further enhanced at higher heating power, preventing large, periodic bursts of the plasma, i.e., edge-localized modes, in the edge region, consistent with ideal magnetohydrodynamics calculations.

2.
Phys Rev Lett ; 121(7): 075001, 2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30169054

RESUMO

A bifurcative step transition from low-density, high-temperature, attached divertor conditions to high-density, low-temperature, detached divertor conditions is experimentally observed in DIII-D tokamak plasmas as density is increased. The step transition is only observed in the high confinement mode and only when the B×∇B drift is directed towards the divertor. This work reports for the first time a theoretical explanation and numerical simulations that qualitatively reproduce this bifurcation and its dependence on the toroidal field direction. According to the model, the bifurcation is primarily driven by the interdependence of the E×B-drift fluxes, divertor electric potential structure, and divertor conditions. In the attached conditions, strong potential gradients in the low field side (LFS) divertor drive E×B-drift flux towards the high field side divertor, reinforcing low density, high temperature conditions in the LFS divertor leg. At the onset of detachment, reduction in the potential gradients in the LFS divertor leg reduce the E×B-drift flux as well, such that the divertor plasma evolves nonlinearly to high density, strongly detached conditions. Experimental estimates of the E×B-drift fluxes, based on divertor Thomson scattering measurements, and their dependence on the divertor conditions are qualitatively consistent with the numerical predictions. The implications for divertor power exhaust and detachment control in the next step fusion devices are discussed.

3.
J Insect Sci ; 16(1)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27638954

RESUMO

Fopius arisanus (Sonan, 1932) (Hymenoptera: Braconidae) is an egg-larval parasitoid used in control programs of Bactrocera dorsalis (Hendel) and Ceratitis capitata (Wiedemann). In Brazil, C. capitata and Anastrepha fraterculus (Wiedemann) are considered the main tephritid pests of exotic and indigenous fruits. The objective of this study was to study the biology of F. arisanus in C. capitata and A. fraterculus Eggs of the two fruit fly species were used to determine the parasitism rate, number of offspring, emergence rate, sex ratio, adult weight and longevity of male and female F. arisanus These biological parameters were used to develop a fertility life table. We observed higher parasitism and emergence rates of adults, a shorter duration of the egg-adult period and a sex ratio biased to females when F. arisanus was reared in eggs of C. capitata than in those of A. fraterculus However, adults of F. arisanus from eggs of A. fraterculus were heavier and had greater longevity than those obtained from C. capitata eggs. The fertility life table showed better biological and reproductive performance for F. arisanus reared in eggs of C. capitata, although eggs of A. fraterculus also provided positive values for population increase.


Assuntos
Controle Biológico de Vetores , Tephritidae/parasitologia , Vespas/fisiologia , Animais , Brasil , Ceratitis capitata/crescimento & desenvolvimento , Ceratitis capitata/parasitologia , Feminino , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Masculino , Tephritidae/crescimento & desenvolvimento
4.
Phys Rev Lett ; 115(21): 215002, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26636855

RESUMO

In a wide variety of natural and laboratory magnetized plasmas, filaments appear as a result of interchange instability. These convective structures substantially enhance transport in the direction perpendicular to the magnetic field. According to filament models, their propagation may follow different regimes depending on the parallel closure of charge conservation. This is of paramount importance in magnetic fusion plasmas, as high collisionality in the scrape-off layer may trigger a regime transition leading to strongly enhanced perpendicular particle fluxes. This work reports for the first time on an experimental verification of this process, linking enhanced transport with a regime transition as predicted by models. Based on these results, a novel scaling for global perpendicular particle transport in reactor relevant tokamaks such as ASDEX-Upgrade and JET is found, leading to important implications for next generation fusion devices.

5.
Neuroradiology ; 56(12): 1063-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25274137

RESUMO

INTRODUCTION: This study aims to investigate diagnostic sensitivity and reliability for the detection of middle cerebral artery occlusion (MCAO) on non-contrast-enhanced computed tomography (NECT) by visual assessment (VA), Hounsfield unit (HU) measurement, calculation of the Hounsfield unit/hematocrit (HU/Hct) ratio, and combination of visual assessment and attenuation measurement (VA + HU). METHODS: NECT of 18 patients with angiographically proven MCAO and 18 patients without MCAO were reviewed by two blinded observers. Visual assessment of presence or absence of a hyperdense sign was followed by HU measurement of both middle cerebral arteries (MCA). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for VA, HU measurement, HU/Hct ratio, and VA + HU measurement. Receiver operating characteristic curve analysis (ROC) was performed to determine the optimal cut-off values for MCAO using attenuation measurements or HU/Hct ratio. RESULTS: Diagnostic sensitivity/specificity was 63%/91% for VA, 56%/88% for attenuation measurement, 68 %/81 % for HU/Hct ratio, and 75%/78% for VA + HU. ROC curve analysis revealed cut-off values of >42.5 HU for attenuation measurements and >1.12 HU/Hct for HU/Hct ratio. CONCLUSION: Combination of visual assessment with additional attenuation measurement with a cut-off value of 42.5 HU is recommended for most sensitive and reliable detection of MCAO on NECT.


Assuntos
Infarto da Artéria Cerebral Média/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
6.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350477

RESUMO

The filterscope diagnostic on DIII-D utilizes photomultiplier tubes to measure visible light emission from the plasma. The system has undergone a substantial upgrade since previous attempts to cross-calibrate the filterscope with other spectroscopic diagnostics were unsuccessful. The optics now utilize a dichroic mirror to initially split the light at nearly 99% transmission or reflectance for light below or above 550 nm. This allows the system to measure Dα emission without degrading visible light emission from the plasma for wavelengths below 550 nm (to measure Dß, Dγ, W-I, C-III, etc.). Additional optimization of the optical components and calibration techniques reduce the error in the signal up to 10% in some channels compared to previous methods. Cross-calibration measurements with two other high resolution spectroscopic diagnostics now show excellent agreement for the first time. This expands the capabilities of the filterscope system allowing measurement of divertor detachment, emission profiles, edge-localized mode behavior, and plasma-wall interactions. It also enables direct comparisons against calculations from boundary plasma simulations. These were not possible before.

7.
Neuroradiology ; 55(2): 171-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23007858

RESUMO

INTRODUCTION: To compare intra- and inter-observer reliability of aneurysm measurements obtained by a 3D computer-aided technique with standard manual aneurysm measurements in different imaging modalities. METHODS: A total of 21 patients with 29 cerebral aneurysms were studied. All patients underwent digital subtraction angiography (DSA), contrast-enhanced (CE-MRA) and time-of-flight magnetic resonance angiography (TOF-MRA). Aneurysm neck and depth diameters were manually measured by two observers in each modality. Additionally, semi-automatic computer-aided diameter measurements were performed using 3D vessel surface models derived from CE- (CE-com) and TOF-MRA (TOF-com) datasets. Bland-Altman analysis (BA) and intra-class correlation coefficient (ICC) were used to evaluate intra- and inter-observer agreement. RESULTS: BA revealed the narrowest relative limits of intra- and inter-observer agreement for aneurysm neck and depth diameters obtained by TOF-com (ranging between ±5.3 % and ±28.3 %) and CE-com (ranging between ±23.3 % and ±38.1 %). Direct measurements in DSA, TOF-MRA and CE-MRA showed considerably wider limits of agreement. The highest ICCs were observed for TOF-com and CE-com (ICC values, 0.92 or higher for intra- as well as inter-observer reliability). CONCLUSION: Computer-aided aneurysm measurement in 3D offers improved intra- and inter-observer reliability and a reproducible parameter extraction, which may be used in clinical routine and as objective surrogate end-points in clinical trials.


Assuntos
Algoritmos , Angiografia Cerebral/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico , Inteligência Artificial , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Nucl Mater ; 438(Suppl): S522-S525, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30976129

RESUMO

In this work a fully kinetic model of the JET SOL with tungsten divertor plates has been developed. It includes the dynamics of main-ions (D+) and electrons, the neutrals (D, C, W) and the impurity particles (C+m, W+n). Our simulations show extremely low concentration of W impurity. We identify two reasons which are responsible for this effect: (1) for low temperature divertor plasma the energy of most of the main-ions and the impurities in a low-ionization state impinging the divertor plates is below the W-sputtering threshold energy; (2) with increasing temperature the W-sputtering increases, but the potential drop across the divertor plasma increases too, so that most of the W ions are reabsorbed at the divertors.

9.
Eur Radiol ; 22(10): 2229-36, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22585406

RESUMO

OBJECTIVES: To prove the feasibility of using Hounsfield attenuation values at MDCT to detect bone bruises related to sacral insufficiency fractures. METHODS: Twenty-two patients with acute sacrum trauma and no fracture findings at MDCT were included in our prospective study. Two observers independently reviewed CTs regarding visual signs of bone bruises in 132 defined regions of the sacral alae. Interobserver agreement was tested by κ statistics. Subsequently, HU values were obtained in the same regions, and attenuation differences between the two sides were calculated. Validity and reliability were assessed by intraclass correlation coefficient and Bland-Altman analysis. HU differences were subjected to ROC curve analysis to determine sensitivity, specificity, PPV and NPV. MRI served as standard reference. RESULTS: MRI revealed 19 regions with bone bruises and associated sacral insufficiency fractures. HU measurements demonstrated good validity and reliability (r = 0.989). ROC curve analysis exhibited an ideal cutoff value of 35.7 HU density difference between affected and non-affected regions. Visual evaluation revealed moderate agreement (κ = 0.48); diagnostic accuracy was inferior to objective evaluation. CONCLUSIONS: Assessment of differences in bone marrow density by HU measurements is an objective and reliable tool for detection of bone bruises associated with occult sacral insufficiency fractures. KEY POINTS : • Bone bruising is associated with occult sacral insufficiency fractures. • Assessment of differences in bone marrow CT attenuation appears valid and reliable. • Comparative HU measurements of bone marrow allow detection of bone bruises. • Comparative HU measurements have high specificity and negative predictive values. • Comparative HU measurements may make further diagnostic workup with MRI unnecessary.


Assuntos
Medula Óssea/diagnóstico por imagem , Fraturas Fechadas/diagnóstico por imagem , Fraturas de Estresse/diagnóstico por imagem , Sacro/lesões , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Fraturas Fechadas/diagnóstico , Fraturas de Estresse/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fraturas da Coluna Vertebral/diagnóstico
10.
Genes Immun ; 11(6): 458-66, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20445567

RESUMO

Copy number variations (CNVs) were found to contribute massively to the variability of genomes. One of the best studied CNV region is the beta-defensin cluster (DEFB) on 8p23.1. Individual DEFFB copy numbers (CNs) between 2 and 12 were found, whereas low CNs predispose for Crohn's disease. A further level of complexity is represented by sequence variations between copies (multisite variations, MSVs). To address the relation of DEFB CN and MSV to the expression of beta-defensin genes, we analyzed DEFB4 expression in B-lymphoblastoid cell lines (LCLs) and primary keratinocytes (normal human epidermal keratinocyte, NHEK) before and after stimulation with lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). Moreover, we quantified one DEFB4 MSV in DNA and mRNA as a marker for variant-specific expression (VSE) and resequenced a region of approximately 2 kb upstream of DEFB4 in LCLs. We found a strong correlation of DEFB CN and DEFB4 expression in 16 LCLs, although several LCLs with very different CNs exhibit similar expression levels. Quantification of the MSV revealed VSE with consistently lower expression of one variant. Costimulation of NHEKs with TNF-alpha/IFN-gamma leads to a synergistic increase in total DEFB4 expression and suppresses VSE. Analysis of the DEFB4 promoter region showed remarkably high density of sequence variabilities (approximately 1 MSV/41 bp).


Assuntos
Variações do Número de Cópias de DNA/genética , Regulação da Expressão Gênica , beta-Defensinas/biossíntese , beta-Defensinas/genética , Sequência de Bases , Células Cultivadas , Variação Genética/genética , Haplótipos/genética , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética
11.
Phys Rev Lett ; 103(16): 165005, 2009 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19905705

RESUMO

Good alignment of the magnetic field line pitch angle with the mode structure of an external resonant magnetic perturbation (RMP) field is shown to induce modulation of the pedestal electron pressure p(e) in high confinement high rotation plasmas at the DIII-D tokamak with a shape similar to ITER, the next step tokamak experiment. This is caused by an edge safety factor q95 resonant enhancement of the thermal transport, while in contrast, the RMP induced particle pump out does not show a significant resonance. The measured p(e) reduction correlates to an increase in the modeled stochastic layer width during pitch angle variations matching results from resistive low rotation plasmas at the TEXTOR tokamak. These findings suggest a field line pitch angle resonant formation of a stochastic magnetic edge layer as an explanation for the q95 resonant character of type-I edge localized mode suppression by RMPs.

12.
Methods Inf Med ; 48(4): 340-3, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19499145

RESUMO

OBJECTIVES: Segmentation of the left ventricle (LV) is required to quantify LV remodeling after myocardial infarction. Therefore spatiotemporal cine MR sequences including long-axis and short-axis images are acquired. In this paper a new segmentation method for fast and robust segmentation of the left ventricle is presented. METHODS: The new approach considers the position of the mitral valve and the apex as well as the long-axis contours to generate a 3D LV surface model. The segmentation result can be checked and adjusted in the short-axis images. Finally quantitative parameters were extracted. RESULTS: For evaluation the LV was segmented in eight datasets of the same subject by two medical experts using a contour drawing tool and the new segmentation tool. The results of both methods were compared concerning interaction time and intra- and inter-observer variance. The presented segmentation method proved to be fast. The mean difference and standard deviation of all parameters are decreased. In case of intra-observer comparison e.g. the mean ESV difference is reduced from 8.8% to 0.5%. CONCLUSION: A semi-automatic LV segmentation method has been developed that combines long- and short-axis views. Using the presented approach the intra- and interobserver difference as well as the time for the segmentation process are decreased. So the semi-automatic segmentation using long- and short-axis information proved to be fast and robust for the quantification of LV mass and volume properties.


Assuntos
Ventrículos do Coração/fisiopatologia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imagem Cinética por Ressonância Magnética , Remodelação Ventricular , Humanos , Interpretação de Imagem Assistida por Computador , Valva Mitral/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Variações Dependentes do Observador
13.
Methods Inf Med ; 48(2): 216-24, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19283322

RESUMO

OBJECTIVES: Left ventricle (LV) segmentation is required to quantify LV volume and mass parameters. Therefore, spatiotemporal Cine MR sequences in the short and long axis of the heart are acquired. Generally, LV segmentation methods consider short-axis sequences only. The reduced resolution in long-axis direction is one of the main reasons for inaccurate parameter extraction in the apical and basal area. The segmentation approach presented combines short- and long-axis information as well as motion tracking to enable the functional LV analysis in 4D MR Image Data. METHODS: First, anatomical landmarks like the mitral valve and the apex are defined in long-axis views in diastolic and systolic phase in order to specify the upper and lower boundary of the LV. Second, motion field approximation using non-linear registration enables the automatic contour propagation to all time points. Third, intersection planes are defined parallel to the mitral valve plane covering the whole ventricle. Finally, the 4D LV surface model is generated appending all in-plane contours. The segmentation results in short-axis images are checked and adjusted interactively and quantitative parameters are extracted. RESULTS: For evaluation the contours of 19 different datasets were traced by two medical experts using a contour drawing tool and the new segmentation tool. The results were compared to evaluate automatic contour propagation, robustness of the segmentation as well as interaction time. CONCLUSION: The automatic contour propagation enables the fast and reproducible generation of a 4D model for the functional analysis of the heart. The interaction time is decreased from approx. 60 minutes to 10 minutes per case. Inter- and intraobserver differences of the extracted parameters are decreased significantly.


Assuntos
Ventrículos do Coração/patologia , Processamento de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Remodelação Ventricular , Simulação por Computador , Diástole , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Imagem Cinética por Ressonância Magnética/instrumentação , Valva Mitral/patologia , Modelos Teóricos , Reprodutibilidade dos Testes , Sístole
14.
Clin Neuroradiol ; 29(1): 95-100, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28875230

RESUMO

The aim of the study was to evaluate the B­flow sonography (BFS) to image the basal cerebral arteries in newborn infants. For this purpose 34 newborns, who underwent standardized ultrasound of the brain including BFS, color Doppler (CDS) and power Doppler (PDS) techniques were retrospectively assessed. Delineation of the anterior communicating (Acom), the posterior communicating (Pcom), the middle cerebral (M1 and M2 segments), the anterior cerebral (A1 and A2 segments), and the posterior cerebral artery (P1 and P2 segments) were visually scored. Vessel delineation was better with BFS compared with CDS and PDS for the M2 segment (p = 0.0006 and p = 0.0136) and P2 segment (p = 0.0021 and p = 0.0014). Superior detectability was also noted for the Pcom with BFS compared with PDS (p = 0.0062). For all other vessel segments no significant differences were found. In conclusion BFS is feasible to image the basal cerebral arteries in newborns with an equal or better vessel delineation compared with standard vascular ultrasound methods.


Assuntos
Artérias Cerebrais/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Variações Dependentes do Observador , Estudos Retrospectivos , Ultrassonografia/métodos , Ultrassonografia Doppler Transcraniana/métodos
15.
J Hum Nutr Diet ; 21(5): 451-63, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18822064

RESUMO

BACKGROUND: Danish adolescents have poor dietary habits compared to current recommendations. The present study aimed to develop a recommended food intake pattern for adolescents consistent with Danish Dietary Guidelines (DDG), Nordic Nutrition Recommendations (NNR) and dietary preferences. METHODS: The nutrient content of a food intake pattern consistent with DDG was calculated using dietary intake data from a random sample of 11-15-year-old boys (n = 85) and girls (n = 70). A recommended food intake pattern was modelled to meet NNR. The discretionary energy allowance was calculated as the difference between the total energy level and the energy needed to meet recommended nutrient needs. The flexibility of the recommended food intake pattern was tested against various energy requirements and with the inclusion of basic foods with higher sugar and/or fat content. RESULTS: The developed food intake pattern meets all nutrient goals except for vitamin D. At low energy requirements, the intake of iron and selenium is of concern. To fulfil nutrient recommendations, half of the bread/cereals and vegetables consumed should be fibre-rich, and fats should be of plant origin. CONCLUSIONS: The recommended food intake pattern meets most nutrient recommendations and makes it possible to advise on discretionary energy.


Assuntos
Dieta , Preferências Alimentares , Promoção da Saúde , Política Nutricional , Adolescente , Criança , Dinamarca , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Sacarose Alimentar/administração & dosagem , Grão Comestível , Ingestão de Energia , Feminino , Humanos , Ferro da Dieta/administração & dosagem , Masculino , Micronutrientes/administração & dosagem , Necessidades Nutricionais , Selênio/administração & dosagem , Verduras
16.
Minerva Cardioangiol ; 56(2): 237-49, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18319702

RESUMO

Assessment of myocardial viability aims at differentiating between viable and non-viable myocardium. The proof of dysfunctional but viable myocardium is crucial to predict outcome of revascularization after acute (AMI) and chronic myocardial infarction (CMI). Cardiac magnetic resonance imaging (CMRI) offers different options to detect viable myocardium: Measurements of end-diastolic wall thickness by cine-CMRI can be used to depict chronically scarred myocardium, but fails to detect acute myocardial necrosis. Low-dose dobutamine stimulation (LDDS) cine-CMRI analyses the contractile reserve of dysfunctional but viable myocardium under pharmacologic stimulus to identify viable myocardium in AMI and CMI with high specificity. Sensitivity of LDDS cine-CMRI is superior to LDDS echocardiography but reduced in patients with severely impaired left ventricular (LV) function. The delayed-enhancement (DE) technique directly visualises non-viable myocardium due to an altered contrast-media distribution in necrotic and fibrotic tissue. DE-CMRI identifies non-viable myocardium with high spatial resolution independently from LV function. The transmural extent of contrast enhancement in DE-CMRI is used to predict functional recovery after revascularization in AMI and CMI. Furthermore, the amount and pattern of contrast enhancement in DE-CMRI provide important prognostic information in both entities. Recent studies demonstrated the superiority of DE-CMRI compared to single photon emission tomography (SPECT) and positron emission tomography (PET) to assess myocardial viability. Therefore, DE-CMRI is currently recognised as the standard of reference for assessment of myocardial viability. The technical background, clinical application and accuracy of the different CMRI techniques to assess myocardial viability in AMI and CMI are discussed in this work.


Assuntos
Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/diagnóstico , Miocárdio/patologia , Dobutamina , Humanos , Processamento de Imagem Assistida por Computador/métodos , Infarto do Miocárdio/diagnóstico , Valor Preditivo dos Testes , Sensibilidade e Especificidade
17.
AJNR Am J Neuroradiol ; 39(5): 869-874, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29567657

RESUMO

BACKGROUND AND PURPOSE: Angiographic occlusion and retreatment of coiled aneurysms are commonly used as surrogate end points in clinical trials. We aimed to evaluate the influence of aneurysm, patient, and rater characteristics on the confidence of visual evaluation of aneurysm coiling and retreatment decisions. MATERIALS AND METHODS: Twenty-six participants of the Advanced Course in Endovascular Interventional Neuroradiology of the European Society of Neuroradiology were asked to evaluate digital subtraction angiography examinations of patients who had undergone endovascular coiling, by determining the grade of aneurysm occlusion, the change between immediate postprocedural and follow-up angiograms, their level of confidence, the technical difficulty of retreatment, and the best therapeutic approach. The experience, knowledge, and skills of each participant were assessed. The influence of rater and case characteristics on indicated confidence in diagnostic ratings and retreatment recommendations was analyzed. RESULTS: Interrater reliability was moderate regarding the assessment of aneurysm occlusion grade (intraclass correlation coefficient = 0.581) and substantial regarding change (intraclass correlation coefficient = 0.776). Overall confidence in the diagnostic rating was high (median, "very certain"). Confidence was statistically significantly higher in cases that were generally rated as "worse." The odds of recommending retreatment were significantly higher in cases that were generally rated with higher mean confidence. CONCLUSIONS: Although overall confidence in the diagnostic rating was high, our study confirms the suboptimal interrater reliability of visual assessment of aneurysm occlusion as well as retreatment recommendations, rendering both questionable as primary outcome measures. Besides recurrence status, recommendation of retreatment is significantly influenced by patient age, aneurysm neck width, and characteristics of the therapist.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano/terapia , Resultado do Tratamento , Adulto , Idoso , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Reprodutibilidade dos Testes , Retratamento
18.
Neotrop Entomol ; 46(5): 554-560, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28474328

RESUMO

Fopius arisanus (Sonan) is a solitary parasitoid of eggs and the first instar larvae of Tephritidae. Due to the occurrence of Ceratitis capitata (Wiedemann) in various regions and under several climatic conditions, this study aimed to evaluate the effect of different temperatures on the embryonic development (egg-adult) and determine thermal requirements and the number of annual generations F. arisanus on eggs of C. capitata. In the laboratory, eggs of C. capitata (24 h) were submitted to parasitism of F. arisanus during 6 h. Later, the eggs were placed in plastic containers (50 mL) (50 eggs/container) on a layer of artificial diet and packed in chambers at temperatures 15, 18, 20, 22, 25, 28, 30, and 32 ± 1°C, RH 70 ± 10%, and a photophase of 12 h. The largest number of offspring, emergence rate, and weight of adults of F. arisanus were observed at 25°C. The highest sex ratios (sr > 0.75) were recorded at 15 and 18°C, being statistically higher than the temperatures 20°C (0.65), 22°C (0.64), 25°C (0.65), 28°C (0.49), and 30°C (0.47). At 32°C, there was no embryonic development of F. arisanus. The egg-adult period was inversely proportional to temperature. Based on the development of the biological cycle (egg-adult), the temperature threshold (T t) was 10.3°C and thermal constant (K) of 488.34 degree-days, being the number of generations/year directly proportional to the temperature increase. The data show the ability of F. arisanus to adapt to different thermal conditions, which is important for biological control programs of C. capitata.


Assuntos
Ceratitis capitata/parasitologia , Temperatura , Vespas/crescimento & desenvolvimento , Animais , Óvulo/parasitologia
19.
Cell Death Dis ; 7: e2103, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26890142

RESUMO

Neutrophil granulocytes are innate effector cells of the first line of defense against pyogenic bacteria. Neutrophil lifespan is short, is prolonged by pro-inflammatory stimuli, controls functionality of the cells and can determine tissue damage. Experimental analysis of primary neutrophils is difficult because of their short lifespan and lack of possibilities of genetic manipulation. The Hoxb8 system of neutrophil differentiation from immortalized progenitor cells offers the advantage of unlimited production of neutrophils in vitro as well as easy genetic modification. We here use this system to analyze the role of the poorly characterized anti-apoptotic B-cell lymphoma protein 2 (Bcl-2) family member A1/Bfl-1 (Bcl-2-related protein A1) for survival and homeostasis of neutrophils and of neutrophil progenitors. Low constitutive mRNA and protein expression of A1 was detected, while A1 was transiently upregulated early during differentiation. Pro-inflammatory stimuli caused strong, mainly transcriptional, A1 upregulation, in contrast to posttranscriptional regulation of Mcl-1 (induced myeloid leukemia cell differentiation protein). Inhibitor studies showed that phosphoinositide-3 kinase (PI3K)/Akt and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) is required for A1 expression and survival of progenitors and mature neutrophils. ShRNA-mediated constitutive A1 knockdown (KD) impaired maintenance of progenitors. ShRNA experiments further showed that A1 was required early during neutrophil differentiation as well as in mature neutrophils upon pro-inflammatory stimulation. Our data further indicate differential regulation of the two anti-apoptotic proteins A1 and Mcl-1. Relevant findings were confirmed in primary human neutrophils. Our data indicate that A1, in addition to the well-established Mcl-1, substantially contributes to neutrophil survival and homeostasis. A1 may thus be a promising target for anti-inflammatory therapy.


Assuntos
Janus Quinases/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Neutrófilos/citologia , Neutrófilos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Granulócitos/citologia , Granulócitos/metabolismo , Homeostase , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais
20.
PLoS One ; 11(5): e0154531, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27140416

RESUMO

Cellular senescence correlates with changes in the transcriptome. To obtain a complete view on senescence-associated transcription networks and pathways, we assessed by deep RNA sequencing the transcriptomes of five of the most commonly used laboratory strains of human fibroblasts during their transition into senescence. In a number of cases, we verified the RNA-seq data by real-time PCR. By determining cellular protein levels we observed that the age-related expression of most but not all genes is regulated at the transcriptional level. We found that 78% of the age-affected differentially expressed genes were commonly regulated in the same direction (either up- or down-regulated) in all five fibroblast strains, indicating a strong conservation of age-associated changes in the transcriptome. KEGG pathway analyses confirmed up-regulation of the senescence-associated secretory phenotype and down-regulation of DNA synthesis/repair and most cell cycle pathways common in all five cell strains. Newly identified senescence-induced pathways include up-regulation of endocytotic/phagocytic pathways and down-regulation of the mRNA metabolism and the mRNA splicing pathways. Our results provide an unprecedented comprehensive and deep view into the individual and common transcriptome and pathway changes during the transition into of senescence of five human fibroblast cell strains.


Assuntos
Senescência Celular/genética , Sequência Conservada , Fibroblastos/citologia , Fibroblastos/metabolismo , Análise de Sequência de RNA , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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