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1.
Br J Dermatol ; 184(6): 1059-1067, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33131055

RESUMEN

BACKGROUND: Primary cutaneous lymphomas (PCLs) are a heterogeneous group of T-cell (CTCL) and B-cell (CBCL) malignancies. Little is known about their epidemiology at initial presentation in Europe and about potential changes over time. OBJECTIVES: The aim of this retrospective study was to analyse the frequency of PCLs in the French Cutaneous Lymphoma Registry (GFELC) and to describe the demography of patients. METHODS: Patients with a centrally validated diagnosis of primary PCL, diagnosed between 2005 and 2019, were included. RESULTS: The calculated incidence was unprecedently high at 1·06 per 100 000 person-years. The number of included patients increased yearly. Most PCL subtypes were more frequent in male patients, diagnosed at a median age of 60 years. The relative frequency of rare CTCL remained stable, the proportion of classical mycosis fungoides (MF) decreased, and the frequency of its variants (e.g. folliculotropic MF) increased. Similar patterns were observed for CBCL; for example, the proportion of marginal-zone CBCL increased over time. CONCLUSIONS: Changes in PCL frequencies may be explained by the emergence of new diagnostic criteria and better description of the entities in the most recent PCL classification. Moreover, we propose that an algorithm should be developed to confirm the diagnosis of PCL by central validation of the cases.


Asunto(s)
Linfoma de Células B , Linfoma Cutáneo de Células T , Micosis Fungoide , Neoplasias Cutáneas , Europa (Continente) , Humanos , Linfoma Cutáneo de Células T/epidemiología , Masculino , Persona de Mediana Edad , Micosis Fungoide/epidemiología , Sistema de Registros , Estudios Retrospectivos , Neoplasias Cutáneas/epidemiología
2.
Phys Rev Lett ; 110(21): 213201, 2013 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-23745869

RESUMEN

The K shell excitation of H-like uranium (U(91+)) in relativistic collisions with different gaseous targets has been studied at the experimental storage ring at GSI Darmstadt. By performing measurements with different targets as well as with different collision energies, we were able to observe for the first time the effect of electron-impact excitation (EIE) process in the heaviest hydrogenlike ion. The large fine-structure splitting in H-like uranium allowed us to unambiguously resolve excitation into different L shell levels. State-of-the-art calculations performed within the relativistic framework which include excitation mechanisms due to both protons (nucleus) and electrons are in good agreement with the experimental findings. Moreover, our experimental data clearly demonstrate the importance of including the generalized Breit interaction in the treatment of the EIE process.

3.
Nat Rev Cancer ; 1(1): 11-21, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11900248

RESUMEN

Population-based studies have established that long-term intake of non-steroidal anti-inflammatory drugs (NSAIDs), compounds that inhibit the enzymatic activity of cyclooxygenase (COX), reduces the relative risk for developing colorectal cancer. These studies led to the identification of a molecular target, COX-2, that is involved in tumour promotion during colorectal cancer progression. Recent studies in humans indicate that therapy with specific COX-2 inhibitors might be an effective approach to colorectal cancer prevention and treatment.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Neoplasias Colorrectales/prevención & control , Inhibidores de la Ciclooxigenasa/uso terapéutico , Isoenzimas/antagonistas & inhibidores , Animales , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/enzimología , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Modelos Animales de Enfermedad , Humanos , Isoenzimas/fisiología , Proteínas de la Membrana , Prostaglandina-Endoperóxido Sintasas/fisiología , Prostaglandinas/biosíntesis , Receptores de Prostaglandina E/fisiología
4.
Phys Rev Lett ; 108(26): 264801, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-23004992

RESUMEN

We report on a study of the polarization transfer between transversely polarized incident electrons and the emitted x rays for electron-atom bremsstrahlung. By means of Compton polarimetry we performed for the first time an energy-differential measurement of the complete properties of bremsstrahlung emission related to linear polarization, i.e., the degree of linear polarization as well as the orientation of the polarization axis. For the high-energy end of the bremsstrahlung continuum the experimental results for both observables show a high sensitivity on the initial electron spin polarization and prove that the polarization orientation is virtually independent of the photon energy.

5.
Sci Rep ; 12(1): 3980, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35256714

RESUMEN

Experimental data are presented for low-energy singly charged ion transport between two insulating parallel plates. Using a beam intensity of approximately 20 pA, measurements of the incoming and transmitted beams provide quantitative temporal information about the charge deposited on the plates and the guiding probability. Using a smaller beam intensity (~ 1 pA) plate charging and discharging properties were studied as a function of time. These data imply that both the charge deposition and decay along the surface and through the bulk need to be modeled as acting independently. A further reduction of beam intensity to ~ 25 fA allowed temporal imaging studies of the positions and intensities of the guided beam plus two bypass beams to be performed. SIMION software was used to simulate trajectories of the guided and bypass beams, to provide information about the amount and location of deposited charge and, as a function of charge patch voltage, the probability of beam guiding and how much the bypass beams are deflected plus to provide information about the electric fields. An equivalent electric circuit model of the parallel plates, used to associate the deposited charge with the patch voltage implies that the deposited charge is distributed primarily on the inner surface of the plates, transverse to the beam direction, rather than being distributed throughout the entire plate.

6.
Phys Rev Lett ; 104(16): 163201, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20482046

RESUMEN

Triply differential single ionization of Ar by 200 eV positron and electron impact is measured and calculated. For an unequivocal test of kinematic differences, fully differential ejected electron angular distributions are measured using the same experimental apparatus and conditions for both positron and electron impact. The binary/recoil intensity ratios are shown to significantly differ for the two projectiles. These data are used to test theoretical calculations.

7.
Phys Rev Lett ; 104(10): 101101, 2010 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-20366411

RESUMEN

We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.

8.
Phys Rev Lett ; 104(9): 091302, 2010 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-20366979

RESUMEN

Dark matter (DM) particle annihilation or decay can produce monochromatic gamma rays readily distinguishable from astrophysical sources. gamma-ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a gamma-ray line analysis, and integrated over most of the sky. We obtain gamma-ray line flux upper limits in the range 0.6-4.5x10{-9} cm{-2} s{-1}, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed.

9.
Phys Rev Lett ; 103(25): 251101, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-20366246

RESUMEN

The diffuse galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission greater, > or approximately equal to 1 GeV relative to diffuse galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10 degrees < or = |b| < or = 20 degrees. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.

10.
Science ; 271(5257): 1864-7, 1996 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-8596955

RESUMEN

Mice homozygous for the barrelless (brl) mutation, mapped here to chromosome 11, lack barrel-shaped arrays of cell clusters termed "barrels" in the primary somatosensory cortex. Deoxyglucose uptake demonstrated that the topology of the cortical whisker representation is nevertheless preserved. Anterograde tracers revealed a lack of spatial segregation of thalamic afferents into individual barrel territories, and single-cell recordings demonstrated a lack of temporal discrimination of center from surround information. Thus, structural segregation of thalamic inputs is not essential to generate topological order in the somatosensory cortex, but it is required for discrete spatiotemporal relay of sensory information to the cortex.


Asunto(s)
Corteza Somatosensorial/fisiología , Vibrisas/inervación , Animales , Axones/ultraestructura , Encéfalo/citología , Encéfalo/metabolismo , Mapeo Cromosómico , Desoxiglucosa/metabolismo , Ratones , Ratones Mutantes , Vías Nerviosas , Neuronas/citología , Neuronas/fisiología , Fenotipo , Corteza Somatosensorial/citología , Corteza Somatosensorial/metabolismo , Tálamo/citología , Tálamo/fisiología , Vibrisas/fisiología
11.
Endoscopy ; 41(3): 200-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280531

RESUMEN

BACKGROUND AND STUDY AIMS: To summarize the published literature on assessment of appropriateness of colonoscopy for screening for colorectal cancer (CRC) in asymptomatic individuals without personal history of CRC or polyps, and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS: A systematic search of guidelines, systematic reviews, and primary studies regarding colonoscopy for screening for colorectal cancer was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy in these circumstances. RESULTS: Available evidence for CRC screening comes from small case-controlled studies, with heterogeneous results, and from indirect evidence from randomized controlled trials (RCTs) on fecal occult blood test (FOBT) screening and studies on flexible sigmoidoscopy screening. Most guidelines recommend screening colonoscopy every 10 years starting at age 50 in average-risk individuals. In individuals with a higher risk of CRC due to family history, there is a consensus that it is appropriate to offer screening colonoscopy at < 50 years. EPAGE II considered screening colonoscopy appropriate above 50 years in average-risk individuals. Panelists deemed screening colonoscopy appropriate for younger patients, with shorter surveillance intervals, where family or personal risk of colorectal cancer is higher. A positive FOBT or the discovery of adenomas at sigmoidoscopy are considered appropriate indications. CONCLUSIONS: Despite the lack of evidence based on randomized controlled trials (RCTs), colonoscopy is recommended by most published guidelines and EPAGE II criteria available online (http://www.epage.ch), as a screening option for CRC in individuals at average risk of CRC, and undisputedly as the main screening tool for CRC in individuals at moderate and high risk of CRC.


Asunto(s)
Colonoscopía , Neoplasias Colorrectales/patología , Europa (Continente) , Guías como Asunto , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Endoscopy ; 41(3): 209-17, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280532

RESUMEN

BACKGROUND AND STUDY AIMS: To summarize the published literature on assessment of appropriateness of colonoscopy for surveillance after polypectomy and after curative-intent resection of colorectal cancer (CRC), and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS: A systematic search of guidelines, systematic reviews and primary studies regarding the evaluation and management of surveillance colonoscopy after polypectomy and after resection of CRC was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy for these conditions. RESULTS: Most CRCs arise from adenomatous polyps. The characteristics of removed polyps, especially the distinction between low-risk adenomas (1 or 2, small [< 1 cm], tubular, no high-grade dysplasia) vs. high-risk adenomas (large [> or = 1 cm], multiple [> 3], high-grade dysplasia or villous features), have an impact on advanced adenoma recurrence. Most guidelines recommend a 3-year follow-up colonoscopy for high-risk adenomas and a 5-year colonoscopy for low-risk adenomas. Despite the lack of evidence to support or refute any survival benefit for follow-up colonoscopy after curative-intent CRC resection, surveillance colonoscopy is recommended by most guidelines. The timing of the first surveillance colonoscopy differs. The expert panel considered that 56 % of the clinical indications for colonoscopy for surveillance after polypectomy were appropriate. For surveillance after CRC resection, it considered colonoscopy appropriate 1 year after resection. CONCLUSIONS: Colonoscopy is recommended as a first-choice procedure for surveillance after polypectomy by all published guidelines and by the EPAGE II criteria. Despite the limitations of the published studies, colonoscopy is also recommended by most of the guidelines and by EPAGE II criteria for surveillance after curative-intent CRC resection.


Asunto(s)
Colonoscopía , Neoplasias Colorrectales/cirugía , Pólipos Intestinales/cirugía , Europa (Continente) , Guías como Asunto , Humanos , Periodo Posoperatorio
13.
Endoscopy ; 41(3): 218-26, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280533

RESUMEN

BACKGROUND AND STUDY AIMS: To summarize the published literature on assessment of appropriateness of colonoscopy for investigation of chronic diarrhea, management of patients with known inflammatory bowel disease (IBD), and for colorectal cancer (CRC) surveillance in such patients, and to report report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS: A systematic search of guidelines, systematic reviews, and primary studies regarding the evaluation of chronic diarrhea, the management of IBD, and colorectal cancer surveillance in IBD was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy for these conditions. RESULTS: According to the literature, colonoscopic evaluation may be justified for patients aged > 50 years with recent-onset chronic diarrhea or with alarm symptoms. Surveillance colonoscopy for CRC should be offered to all patients with extensive ulcerative colitis or colonic Crohn's disease of 8 years' duration, and to all patients with less extensive disease of 15 years' duration. Intervals for surveillance colonoscopy depend on duration of evolution, initial diagnosis, and histological findings. The EPAGE II criteria also confirmed the appropriateness of diagnostic colonoscopy for diarrhea of > 4 weeks' duration. They also suggest that, in addition to assessing extent of IBD by colonoscopy, further colonoscopic examination is appropriate in the face of persistent or worsening symptoms. Surveillance colonoscopy in IBD patients was generally appropriate after a lapse of 2 years. In the presence of dysplasia at previous colonoscopy, it was not only appropriate but necessary. CONCLUSIONS: Despite or perhaps because of the limitations of the available published studies, the panel-based EPAGE II (http://www.epage.ch) criteria can help guide appropriate colonoscopy use in the absence of strong evidence from the literature.


Asunto(s)
Colonoscopía , Diarrea/patología , Enfermedades Inflamatorias del Intestino/patología , Enfermedad Crónica , Neoplasias Colorrectales/patología , Europa (Continente) , Guías como Asunto , Humanos
14.
Endoscopy ; 41(3): 240-6, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280536

RESUMEN

BACKGROUND AND STUDY AIMS: Appropriate use of colonoscopy is a key component of quality management in gastrointestinal endoscopy. In an update of a 1998 publication, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE II) defined appropriateness criteria for various colonoscopy indications. This introductory paper therefore deals with methodology, general appropriateness, and a review of colonoscopy complications. METHODS: The RAND/UCLA Appropriateness Method was used to evaluate the appropriateness of various diagnostic colonoscopy indications, with 14 multidisciplinary experts using a scale from 1 (extremely inappropriate) to 9 (extremely appropriate). Evidence reported in a comprehensive updated literature review was used for these decisions. Consolidation of the ratings into three appropriateness categories (appropriate, uncertain, inappropriate) was based on the median and the heterogeneity of the votes. The experts then met to discuss areas of disagreement in the light of existing evidence, followed by a second rating round, with a subsequent third voting round on necessity criteria, using much more stringent criteria (i. e. colonoscopy is deemed mandatory). RESULTS: Overall, 463 indications were rated, with 55 %, 16 % and 29 % of them being judged appropriate, uncertain and inappropriate, respectively. Perforation and hemorrhage rates, as reported in 39 studies, were in general < 0.1 % and < 0.3 %, respectively CONCLUSIONS: The updated EPAGE II criteria constitute an aid to clinical decision-making but should in no way replace individual judgment. Detailed panel results are freely available on the internet (www.epage.ch) and will thus constitute a reference source of information for clinicians.


Asunto(s)
Colonoscopía/normas , Colonoscopía/efectos adversos , Colonoscopía/métodos , Europa (Continente) , Humanos , Resultado del Tratamiento
15.
Endoscopy ; 41(3): 227-33, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280534

RESUMEN

BACKGROUND AND STUDY AIMS: To summarize the published literature on assessment of appropriateness of colonoscopy for the investigation of iron-deficiency anemia (IDA) and hematochezia, and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS: A systematic search of guidelines, systematic reviews and primary studies regarding the evaluation and management of IDA and hematochezia was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy for these conditions. RESULTS: IDA occurs in 2 %-5 % of adult men and postmenopausal women. Examination of both the upper and lower gastrointestinal tract is recommended in patients with iron deficiency. Colonoscopy for IDA yields one colorectal cancer (CRC) in every 9-13 colonoscopies. Hematochezia is a well-recognized alarm symptom and such patients are likely to be referred for colonoscopy. Colonoscopy is unanimously recommended in patients aged > or = 50. Diverticulosis, vascular ectasias, and ischemic colitis are common causes of acute lower gastrointestinal bleeding (LGIB); CRC is found in 0.2 %-11 % of the colonoscopies performed for LGIB. Most patients with scant hematochezia have an anorectal or a distal source of bleeding. The expert panel considered most clinical indications for colonoscopy as appropriate in the presence of IDA (58 %) or hematochezia (83 %). CONCLUSION: Despite the limitations of the published studies, guidelines unanimously recommend colonoscopy for the investigation of IDA and hematochezia in patients aged > or = 50 years. These indications were also considered appropriate by EPAGE II, as were indications in patients at low risk for CRC with no obvious cause of bleeding found during adequate previous investigations.


Asunto(s)
Anemia Ferropénica/patología , Colonoscopía , Hemorragia Gastrointestinal/patología , Europa (Continente) , Femenino , Guías como Asunto , Humanos , Masculino , Persona de Mediana Edad
16.
Endoscopy ; 41(3): 234-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19280535

RESUMEN

BACKGROUND AND STUDY AIMS: To summarize the published literature on assessment of appropriateness of colonoscopy for the investigation of functional bowel symptoms, and report appropriateness criteria developed by an expert panel, the 2008 European Panel on the Appropriateness of Gastrointestinal Endoscopy, EPAGE II. METHODS: A systematic search of guidelines, systematic reviews and primary studies regarding the evaluation and management of functional bowel symptoms was performed. The RAND/UCLA Appropriateness Method was applied to develop appropriateness criteria for colonoscopy for these conditions. RESULTS: Much of the evidence for use of colonoscopy in evaluation of chronic abdominal pain, and/or constipation and/or abdominal bloating is modest. Major limitations include small numbers of patients and lack of adequate characterization of these patients. Large community-based follow-up studies are needed to enable better definition of the natural history of patients with functional bowel disorders. Guidelines stress that alarm features ("red flags"), such as rectal bleeding, anemia, weight loss, nocturnal symptoms, family history of colon cancer, age of onset > 50 years, and recent onset of symptoms should all lead to careful evaluation before a diagnosis of functional bowel disorder is made. EPAGE II assessed these symptoms by means of 12 clinical scenarios, rating colonoscopy as appropriate, uncertain and inappropriate in 42 % (5/12), 25 % (3/12), and 33 % (4/12) of these, respectively. CONCLUSIONS: Evidence to support the use of colonoscopy in the evaluation of patients with functional bowel disorders and no alarm features is lacking. These patients have no increased risk of colon cancer and thus advice on screening for this is not different from that for the general population. EPAGE II criteria, available online (http://www.epage.ch), consider colonoscopy appropriate in patients of > 50 years with chronic or new-onset bowel disturbances, but not in patients with isolated chronic abdominal pain.


Asunto(s)
Dolor Abdominal/patología , Colonoscopía , Enfermedades Intestinales/patología , Estreñimiento/patología , Europa (Continente) , Guías como Asunto , Humanos , Persona de Mediana Edad
17.
Eur Ann Otorhinolaryngol Head Neck Dis ; 136(1): 47-49, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30712651

RESUMEN

INTRODUCTION: Kimura disease (KD) is a chronic lymphoproliferative disorder of unknown etiology that affects the skin and lymph nodes, mostly observed in males of Asian descent. The natural history of asymptomatic epiglottal KD remains unknown. This rare site of KD is often only diagnosed when tumor growth starts to obstruct the upper airways. OBSERVATION: A 34-year-old North African male presented with fatigue and multiple, slowly progressive, fluctuating skin nodules in the right mandibular and retroauricular regions. Computed tomography of the head and neck revealed a large soft tissue tumor close to the right mandibular body and unexpected thickening of the epiglottis. Transnasal laryngoscopy confirmed the CT findings and showed thickening of the epiglottis. The diagnosis of KD was based on histological examination of biopsy specimens taken from the right mandibular tumor, a cervical lymph node, and the epiglottis. DISCUSSION: Most cases of KD with epiglottal involvement present with dysphonia and dysphagia. No consensus guidelines are available concerning the complementary investigations that should be performed. This case report raises the question of whether patients with suspected KD should be systematically screened for lesions in unusual and potentially dangerous anatomic sites.


Asunto(s)
Hiperplasia Angiolinfoide con Eosinofilia/diagnóstico por imagen , Epiglotis/diagnóstico por imagen , Enfermedades de la Laringe/diagnóstico por imagen , Adulto , Enfermedades Asintomáticas , Humanos , Laringoscopía , Masculino , Tomografía Computarizada por Rayos X
18.
Sci Rep ; 9(1): 6100, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30988343

RESUMEN

Quantifying tumor burden is important for following the natural history of orthotopic colon cancer and therapeutic efficacy. Bioluminescence imaging (BLI) is commonly used for such assessment and has both advantages and limitations. We compared BLI and magnetic resonance imaging (MRI) for quantifying orthotopic tumors in a mouse model of colon cancer. Among sequences tested, T2-based MRI imaging ranked best overall for colon cancer border delineation, contrast, and conspicuity. Longitudinal MRI detected tumor outside the colon, indistinguished by BLI. Colon tumor weights calculated from MRI in vivo correlated highly with tumor weights measured ex vivo whereas the BLI signal intensities correlated relatively poorly and this difference in correlations was highly significant. This suggests that MRI may more accurately assess tumor burden in longitudinal monitoring of orthotopic colon cancer in this model as well as in other models.


Asunto(s)
Neoplasias del Colon/diagnóstico por imagen , Mediciones Luminiscentes , Imagen por Resonancia Magnética , Animales , Células HCT116 , Humanos , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias
19.
Artículo en Inglés | MEDLINE | ID: mdl-32123686

RESUMEN

Electrocardiographic Imaging (ECGI) aims to reconstruct electrograms from the body surface potential measurements. Bad leads are usually excluded from the inverse problem solution. Alternatively, interpolation can be applied. This study explores how sensitive ECGI is to different bad-lead configurations and interpolation methods. Experimental data from a Langendorff-perfused pig heart suspended in a human-shaped torso-tank was used. Epicardial electrograms were acquired during 30 s (31 beats) of RV pacing using a 108-electrode array, simultaneously with torso potentials from 128 electrodes embedded in the tank surface. Six different bad lead cases were designed based on clinical experience. Inverse problem was solved by applying Tikhonov regularization i) using the complete data, ii) bad-leads-removed data, and iii) interpolated data, with 5 different methods. Our results showed that ECGI accuracy of an interpolation method highly depends on the location of the bad leads. If they are in the high-potential-gradient regions of the torso, a highly accurate interpolation method is needed to achieve an ECGI accuracy close to using complete data. If the BSP reconstruction of the interpolation method is poor in these regions, the reconstructed electrograms also have lower accuracy, suggesting that bad leads should be removed instead of interpolated. The inverse-forward method was found to be the best among all interpolation methods applied in this study in terms of both missing BSP lead reconstruction and ECGI accuracy, even for the bad leads located over the chest.

20.
Rheumatology (Oxford) ; 47(2): 194-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18178593

RESUMEN

OBJECTIVES: There is a lack of agreement on assessing disease activity in patients with RA and determining when the RA treatment should be changed or continued. A panel of rheumatologists was convened to develop guidelines to assess adequacy of disease control, focusing on the use of disease-modifying anti-rheumatic drugs. METHODS: The Research and Development/University of California in Los Angeles (RAND/UCLA) Appropriateness Method was used to evaluate disease control adequacy. After a literature review, 108 scenarios were developed to simulate situations most likely to be encountered in clinical practice and rated on a 9-point scale by a 10-member expert panel. RESULTS: Final appropriateness rankings for the scenarios were as follows: 37% 'appropriate', 48% 'inappropriate', and 16% 'neutral'. The panelists felt that patients with disease control in the 'appropriate' range have adequate control with their current therapy, whereas those in the 'inappropriate' range should be considered for a change in therapy. Those in 'neutral' areas should have their therapy reviewed carefully. The panelists recommended that the clinically active joint count should be considered the most important decision factor. In patients with no clinically active joints, regardless of other factors no change in therapy was felt to be warranted. Patients with five or more active joints should be considered inadequately treated, and in patients with one to four active joints other variables must be considered in the decision to change therapy. CONCLUSION: These preliminary guidelines will assist the clinician in determining when a patient's clinical situation warrants therapy escalation and when continuing the current regimen would be appropriate.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Antiinflamatorios no Esteroideos/uso terapéutico , Antirreumáticos/clasificación , Antirreumáticos/normas , Ensayos Clínicos como Asunto/normas , Atención a la Salud , Estudios de Evaluación como Asunto , Medicina Basada en la Evidencia , Humanos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Resultado del Tratamiento
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