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We show in experiments that a long, underdense, relativistic proton bunch propagating in plasma undergoes the oblique instability, which we observe as filamentation. We determine a threshold value for the ratio between the bunch transverse size and plasma skin depth for the instability to occur. At the threshold, the outcome of the experiment alternates between filamentation and self-modulation instability (evidenced by longitudinal modulation into microbunches). Time-resolved images of the bunch density distribution reveal that filamentation grows to an observable level late along the bunch, confirming the spatiotemporal nature of the instability. We provide a rough estimate of the amplitude of the magnetic field generated in the plasma by the instability and show that the associated magnetic energy increases with plasma density.
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OBJECTIVES: Concurrent anomalies are often found in nasopharyngeal stenosis and choanal atresia; some seem to be of primary nature, whereas others may be coincidental. This study aimed to report the computed tomography features and related comorbidities of these diseases. MATERIALS AND METHODS: A cross-sectional retrospective study was performed using case and control groups defined according to the presence of signs of upper airway disease and the presence/absence of nasopharyngeal stenosis, respectively. The inclusion criteria were full-head tomography scans and access to clinical records. The exclusion criteria were brachycephalic breed, head trauma and neoplasm. Clinical and computed tomographic findings and relevant comorbidities were recorded. RESULTS: Forty-three cats were included, 23 cases and 20 controls. The case group was significantly younger, had more paranasal sinus anomalies and never had turbinate lysis, also, had significantly more soft palate anomalies, which was significantly shorter. Nasopharyngeal stenosis varied from membrane appearance to partial or complete adhesion of the soft palate to the nasopharynx, was mainly located in the caudal region of the nasopharynx and was imperforated in approximately half of the cases. Imperforated membranes were significantly thicker in the sagittal plane and were significantly associated with nasal obstruction and soft tissue attenuation of the tympanic bulla. Hiatal hernia and ventricular asymmetry were only encountered in three and two cases, respectively, with nasopharyngeal stenosis. CLINICAL SIGNIFICANCE: Computed tomography in cats with nasopharyngeal stenosis can identify concurrent anomalies, can help to differentiate a possible choanal atresia and evaluate the magnitude of its significance.
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Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.
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Dorsal-ventral (DV) patterning is regulated by the bone morphogenetic pathway (BMP) in Bilateria. In insect DV patterning, the Toll pathway also plays a role, in addition to BMPs. Variations in the relative importance of each pathway for DV patterning have been reported using single species of coleopteran, hymenopteran, hemipteran and orthopteran insects. To investigate if the molecular control of DV patterning is conserved inside an insect order, the emergent model hemiptera species Rhodnius prolixus was studied. We found that R. prolixus BMP pathway controls the entire DV axis, with a broader effect respective to Toll, as shown for the hemiptera Oncopeltus fasciatus. Different from O. fasciatus, the unique R. prolixus short gastrulation (sog) and the twisted gastrulation (tsg) orthologues do not antagonize, but rather favour embryonic BMP signalling. Our results reinforce the hypothesis that hemiptera rely preferentially on BMPs for DV patterning but that, surprisingly, in R. prolixus Sog and Tsg proteins exert only a positive role to establish a dorsal-to-ventral BMP gradient. Since sog has been reported to be lost from orthopteran and hymenopteran genomes, our results indicate that Sog's role to modify BMP activity varies greatly in different insect species.
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Gastrulación , Rhodnius , Animales , Rhodnius/genética , Rhodnius/metabolismo , Proteínas/metabolismo , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Insectos/metabolismo , Tipificación del Cuerpo/genéticaRESUMEN
The effect of annual at-home bleaching on the color, translucency, and whiteness properties of computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic materials requires investigation. The aim of the present in vitro study was to evaluate the effect of simulated annual at-home bleaching (consisting of daily applications for 10 hours a day for 14 days), for up to 3 years, on susceptibility to staining (ΔE00), translucency (ΔTP00), and whiteness (ΔWID) variations and on topography of CAD-CAM monolithic materials. Disks from the Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), and IPS e.max CAD (EMAX) were allocated as follows: 1) nonbleached or 2) bleached with 10% carbamide peroxide. After reading the CIE L*a*b* coordinates at baseline (R0), specimens were bleached or not and subsequently immersed for a 1-year simulated period in coffee before the next reading (R1). This process was repeated two more times, resulting in R2 and R3. The ΔE00, ΔTP00, and ΔWID between R1, R2, and R3 in relation to R0 were calculated. The surface topography was analyzed by scanning electron microscopy. In general, bleaching increased the staining susceptibility of all materials when compared to the nonbleached groups and that of the LU, VE, and EMAX over the years. Bleaching decreased the translucency of the VE in all years and over the years. When compared to the nonbleached groups, bleaching decreased the whiteness of the LU and EMAX and increased the whiteness of the EMP, while the VE was not affected. In the LU, the whiteness decreased over the years in both treatments, whereas the other materials were not affected with time. All materials showed progressive topographic changes over the years. The simulated annual at-home bleaching with 10% carbamide peroxide adversely affected the topography and the optical and/or colorimetric properties of the evaluated materials.
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Cerámica , Diseño Asistido por Computadora , Peróxido de Carbamida , Color , Ensayo de Materiales , Propiedades de Superficie , Coloración y Etiquetado , Porcelana DentalRESUMEN
Little is known about the effects of in-office bleaching on the surface properties and on other aspects of CAD-CAM monolithic materials, especially when successive bleaching sessions are conducted. This study evaluated the effect of up to three successive in-office bleaching sessions on the microhardness, roughness, topography, substance loss, biaxial flexural strength (BFS), and reliability of CAD-CAM monolithic materials. Disks from Lava Ultimate (LU), Vita Enamic (VE), and IPS Empress CAD (EMP) were fabricated and submitted to one, two, and three bleaching sessions. In-office bleaching was performed with 40% hydrogen peroxide and each session consisted of three applications of 20 minutes each. The analyses regarding the aforementioned parameters were assessed before and after the first, second, and third bleaching sessions, except for BFS, which was evaluated at the baseline and after the third session. Weibull modulus was calculated from the BFS data. Bleaching decreased the microhardness of LU and VE from the third and second sessions, respectively, and affected neither the roughness nor the BFS of the three materials. However, in LU, it decreased the reliability and caused topographic changes, which were accentuated by the increase in the number of sessions. In general, LU and EMP showed, respectively, the highest and the lowest substance losses. Successive in-office bleaching sessions with the use of the protocol of the present study should be avoided in LU and VE.
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Cerámica , Resistencia Flexional , Reproducibilidad de los Resultados , Ensayo de Materiales , Diseño Asistido por Computadora , Propiedades de Superficie , Porcelana DentalRESUMEN
A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.
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Diabetes Mellitus (DM) is both, correlated and a known risk factor for colorectal cancer (CRC). Besides favoring the incidence of CRC, DM also accelerates its progression, worsening its prognosis. Previously, hyperglycemia, the DM hallmark, has been shown to lead to aberrant glycosylation of CRC cells, heightening their malignancy both in vivo and in vitro. Here we use mass spectrometry to elucidate the composition and putative structures of N-glycans expressed by MC38 cultured in normoglycemic (LG) and hyperglycemic-like conditions (HG). N-glycans, 67, were identified in MC38 cells cultured in LG and HG. The cells grown in HG showed a greater abundance of N-glycans when compared to LNG cells, without changes in the proportion of sialylated, fucosylated and mannosylated N-glycans. Among the identified N-glycans, 16 were differentially expressed, mostly mannosylated and fucosylated, with a minority of them being sialylated. Metabolomics analysis indicates that the alterations observed in the N-glycosylation may be mostly due to increase of the activated monosaccharides pool, through an increased glucose entrance into the cells. The alterations found here corroborate data from the literature regarding the progression of CRC, advocating for development or repositioning of effective treatments against CRC in diabetic patients.
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Neoplasias del Colon , Hiperglucemia , Glicosilación , Humanos , Monosacáridos/química , Polisacáridos/químicaRESUMEN
The nonlinear evolution of electromagnetic instabilities driven by the interpenetration of two e^{-},e^{+} plasma clouds is explored using ab initio kinetic plasma simulations. We show that the plasma clouds slow down due to both oblique and Weibel generated electromagnetic fields, which deflect the particle trajectories, transferring bulk forward momentum into transverse momentum and thermal velocity spread. This process causes the flow velocity v_{inst} to decrease approximately by a factor of sqrt[1/3] in a time interval Δt_{αB}ω_{p}â¼c/(v_{fl}sqrt[α_{B}]), where α_{B} is the magnetic equipartition parameter determined by the nonlinear saturation of the instabilities, v_{fl} is the initial flow speed, and ω_{p} is the plasma frequency. For the α_{B} measured in our simulations, Δt_{αB} is close to 10 times the instability growth time. We show that as long as the plasma slab length L>v_{fl}Δt_{αB}, the plasma flow is expected to slow down by a factor close to sqrt[1/3].
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INTRODUCTION: Neonatal airway examination through flexible/rigid bronchoscopy has proved to be useful in the presence of persistent stridor and extubation failure, as well as to assess complications following cardiac surgery. At our institution, these examinations are carried out by a pulmonologist, a neonatologist, an otorhinolaryngologist, and a pediatric surgeon from the pediatric airway committee, established in 2014. OBJECTIVE: To analyze the airway examinations performed in neonates during their stay at the neonatology/neonatal intensive care unit since the airway committee was established. MATERIAL AND METHODS: A retrospective study of the airway examinations conducted in neonates from 2015 to 2019 was carried out. Clinical and demographic data, number of examinations, indications, findings, and complications were collected. Results are presented as mean and standard deviation. Statistical significance was established at p < 0.05. RESULTS: 92 airway examinations were analyzed in 51 patients (54.9% of whom were female). 51% of the patients were premature. Extubation failure and persistent respiratory symptoms following successful extubation were the most frequent indications for airway examination (35.3%). Stratification by gestational age or weight at birth was not associated with an increased risk of pathological findings at examination (p > 0.05). The most frequent finding was vocal cord paralysis (n = 14; 27.5%). In 10 patients (19.6%), no pathological findings were observed. CONCLUSION: Airway examination is useful in patients with stridor to identify vocal cord paralysis following extubation failure. It also allows congenital airway pathologies to be diagnosed and treated. The number of examinations with no pathological findings was similar to that reported in international series.
INTRODUCCION: La exploración de vía aérea mediante broncoscopia flexible/rígida en el neonato ha demostrado utilidad en el estridor persistente, extubaciones fallidas o para valorar complicaciones tras cirugía cardiaca. En nuestro hospital estas exploraciones son practicadas por un neumólogo, neonatólogo, otorrinolaringólogo y cirujano pediátrico del Comité de Vía Aérea Pediátrica, formado en 2014. OBJETIVO: Analizar las exploraciones de vía aérea practicadas a neonatos durante su estancia en Neonatología/Unidad de Cuidados Intensivos Neonatales desde la constitución del Comité de Vía Aérea. MATERIAL Y METODOS: Estudio retrospectivo de exploraciones de vía aérea practicadas a neonatos de 2015-2019. Se recogen datos clínicos y demográficos, número de exploraciones, indicación, hallazgos y complicaciones. Se presentan las medias con su desviación estándar. Se consideró un resultado estadísticamente significativo cuando p < 0,05. RESULTADOS: Se analizaron 92 exploraciones de vía aérea en 51 pacientes (género femenino: 54,9%). El 51% de los pacientes fueron prematuros. La extubación fallida y la persistencia de sintomatología respiratoria tras una extubación satisfactoria fueron las indicaciones más frecuentes (35,3%). La estratificación por edad gestacional o por peso al nacimiento no se asociaba a un mayor riesgo de presentar hallazgos patológicos en la exploración. El hallazgo más frecuente fue la parálisis de cuerda vocal (n = 14; 27,5%). En 10 pacientes (19,6%) no se encontraron hallazgos patológicos. CONCLUSION: La exploración de la vía aérea es útil en pacientes con estridor postextubación y para identificar parálisis de cuerda vocal tras extubación fallida. Además, permite el diagnóstico y tratamiento de patologías congénitas de la vía aérea.
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Extubación Traqueal , Broncoscopía , Niño , Femenino , Hospitales , Humanos , Lactante , Recién Nacido , Ruidos Respiratorios , Estudios RetrospectivosRESUMEN
Little is known about the impact of bleaching on the optical properties of computer-aided design and computer-aided manufactured (CAD-CAM) monolithic materials. The aim of the present study was to evaluate the effect of one session of in-office bleaching on stain removal, staining susceptibility, translucency, and whiteness variations of CAD-CAM monolithic materials. Disks were fabricated from Lava Ultimate (LU), Vita Enamic (VE), Vita Suprinity (VS), and IPS e.max CAD (IPS). A spectrophotometer was used to register Commission Internationale de l'Eclairage L*a*b* coordinates. For stain removal, 80 specimens from each material were assessed at baseline (R0) and after immersion in deionized water or coffee for 36.5 days followed or not by bleaching with 40% hydrogen peroxide (R1). For staining susceptibility, 80 specimens from each material were analyzed at baseline (R0'), and after having been bleached or not and immersed in deionized water or coffee (R1'). Both analyses were calculated as the color difference (ΔE00) between R1-R0 and R1'-R0', respectively. Differences in translucency (ΔTP00) and whiteness (ΔWID) between R1-R0 and R1'-R0' were also calculated. Data were analyzed by three-way ANOVA and the Games-Howell post hoc test (α=0.05). Clinical significance was based on 50%:50% perceptibility and acceptability thresholds for ΔE00, ΔTP00 and ΔWID, respectively. Surfaces were analyzed by scanning electron microscopy. Coffee increased ΔE00 in LU, VE, and VS, and decreased their translucency and whiteness, whereas the IPS had only its whiteness affected. Bleaching after immersion in coffee decreased ΔE00 in LU and VE, and increased translucency and whiteness of LU, VE, and VS. No effect was observed on IPS. Bleaching before immersion in coffee decreased translucency of LU, but within the acceptable interval, while VE exhibited lower ΔE00, and became more translucent and less dark. Both VS and IPS were not affected. One session of in-office bleaching benefited optical properties of the previously stained LU, VE, and VS, without increasing their susceptibility to staining or adversely providing clinically unacceptable variations in their translucency and whiteness. All variations exhibited by the IPS were below the perceptible threshold.
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Cerámica , Resinas Compuestas , Color , Diseño Asistido por Computadora , Porcelana Dental , Ensayo de Materiales , Propiedades de SuperficieRESUMEN
Introducción: La exploración de vía aérea mediante broncoscopiaflexible/rígida en el neonato ha demostrado utilidad en el estridor persistente, extubaciones fallidas o para valorar complicaciones tras cirugíacardiaca. En nuestro hospital estas exploraciones son practicadas porun neumólogo, neonatólogo, otorrinolaringólogo y cirujano pediátricodel Comité de Vía Aérea Pediátrica, formado en 2014. Objetivo: Analizar las exploraciones de vía aérea practicadas aneonatos durante su estancia en Neonatología/Unidad de CuidadosIntensivos Neonatales desde la constitución del Comité de Vía Aérea.Materiales. Estudio retrospectivo de exploraciones de vía aéreapracticadas a neonatos en el periodo 2015-2019. Se recogen datosclínicos y demográficos, número de exploraciones, indicación, hallazgos y complicaciones. Se presentan las medias con su desviaciónestándar. Se consideró un resultado estadísticamente significativocuando p < 0,05. Resultados: Se analizaron 92 exploraciones de vía aérea en 51pacientes (género femenino: 54,9%). El 51% de los pacientes fueronprematuros. La extubación fallida y la persistencia de sintomatologíarespiratoria tras una extubación satisfactoria fueron las indicacionesmás frecuentes (35,3%). La estratificación por edad gestacional o porpeso al nacimiento no se asociaba a un mayor riesgo de presentar ha-llazgos patológicos en la exploración. El hallazgo más frecuente fue laparálisis de cuerda vocal (n = 14; 27,5%). En 10 pacientes (19,6%) nose encontraron hallazgos patológicos. Conclusión: La exploración de la vía aérea es útil en pacientes conestridor postextubación y para identificar parálisis de cuerda vocal trasextubación fallida. Además, permite el diagnóstico y tratamiento depatologías congénitas de la vía aérea.(AU)
Introduction: Neonatal airway examination through flexible/rigid bronchoscopy has proved to be useful in the presence of persis-tent stridor and extubation failure, as well as to assess complicationsfollowing cardiac surgery. At our institution, these examinations arecarried out by a pulmonologist, a neonatologist, an otorhinolaryngolo-gist, and a pediatric surgeon from the pediatric airway committee,established in 2014. Objective: To analyze the airway examinations performed in neo-nates during their stay at the neonatology/neonatal intensive care unitsince the airway committee was established.Materials and methods. A retrospective study of the airway ex-aminations conducted in neonates from 2015 to 2019 was carried out.Clinical and demographic data, number of examinations, indications,findings, and complications were collected. Results are presented asmean and standard deviation. Statistical significance was establishedat p < 0.05. Results: 92 airway examinations were analyzed in 51 patients(54.9% of whom were female). 51% of the patients were premature.Extubation failure and persistent respiratory symptoms followingsuccessful extubation were the most frequent indications for airwayexamination (35.3%). Stratification by gestational age or weight atbirth was not associated with an increased risk of pathological findingsat examination (p > 0.05). The most frequent finding was vocal cordparalysis (n = 14; 27.5%). In 10 patients (19.6%), no pathologicalfindings were observed. Conclusion: Airway examination is useful in patients with stridorto identify vocal cord paralysis following extubation failure. It alsoallows congenital airway pathologies to be diagnosed and treated. Thenumber of examinations with no pathological findings was similar tothat reported in international series.(AU)
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Humanos , Masculino , Femenino , Recién Nacido , Manejo de la Vía Aérea , Broncoscopía , Pliegues Vocales/lesiones , Extubación Traqueal , Cirugía General , Pediatría , Estudios RetrospectivosRESUMEN
INTRODUCTION: Graft-versus-host disease (GVHD) is a frequent complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), with high morbidity and mortality rates. Intestinal clinical signs are unspecific, which means differential diagnosis with infections and drug-related etiology should be carried out. Even though intestinal biopsy is widely considered as the gold standard technique, there is no consensus as to which sampling method is best. OBJECTIVE: To assess the results of the biopsy techniques used in patients with suspected intestinal GVHD. MATERIAL AND METHODS: A retrospective study of patients with suspected intestinal GVHD undergoing allo-HSCT from 2010 to 2019 was carried out. They were assessed through digestive biopsy - esophagogastroduodenal biopsy (upper GI endoscopy - UGIE) or rectal biopsy (colonoscopy or direct biopsy). Quantitative variables, expressed as median and interquartile range, and qualitative variables, expressed as absolute frequency and percentage, were collected. RESULTS: 23 patients were studied, 60.9% of whom were male. Median age at biopsy was 9 years (7-14 years). UGIE was used in 47.8% of patients (n=11), colonoscopy was used in 26.1% of patients (n=6), and direct biopsy was used in 34.8% of patients (n=8), with GVHD positive results in 2 (18.2%), 2 (33.3%), and 4 (50%) patients, respectively. CONCLUSIONS: Samples taken through direct biopsy stand as an effective alternative in GVHD diagnosis.
INTRODUCCION: La enfermedad injerto contra huésped (EICH) es una complicación frecuente de los trasplantes de células precursoras hematopoyéticas alogénicos (alo-TCPH), con gran morbimortalidad. La clínica intestinal es inespecífica, planteando el diagnóstico diferencial con infecciones y etiología medicamentosa. Aunque las biopsias intestinales son el gold standard, no existe consenso sobre la mejor técnica para obtenerlas. OBJETIVO: Evaluar los resultados de las técnicas empleadas para obtener biopsias en pacientes con sospecha de EICH intestinal. MATERIAL Y METODOS: Estudio retrospectivo que incluye pacientes sometidos a alo-TCPH entre 2010 y 2019, con sospecha de EICH intestinal estudiados mediante biopsias digestivas: esofagogastroduodenales (endoscopia digestiva alta - EDA) o rectales (colonoscopia o biopsia directa). Recogimos variables cuantitativas, expresadas como mediana y rango intercuartílico; y cualitativas, expresadas en frecuencia absoluta y porcentaje. RESULTADOS: Estudiamos 23 pacientes (60,9% varones). La mediana de edad en el momento de la biopsia fue 9 años (7-14 años). Empleamos EDA en el 47,8% (n=â¯11), colonoscopia en 26,1% (n=â¯6) y biopsia directa en el 34,8% (n=â¯8); siendo positivas para EICH en 2 (18,2%), 2 (33,3%) y 4 (50%), respectivamente. CONCLUSIONES: Las muestras obtenidas mediante biopsia directa se plantean como una alternativa eficiente en el diagnóstico del EICH.
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Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Biopsia , Colonoscopía , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Masculino , Estudios RetrospectivosRESUMEN
Introducción: La enfermedad injerto contra huésped (EICH) esuna complicación frecuente de los trasplantes de células precursorashematopoyéticas alogénicos (alo-TCPH), con gran morbimortalidad.La clínica intestinal es inespecífica, planteando el diagnóstico diferencial con infecciones y etiología medicamentosa. Aunque las biopsiasintestinales son el gold standard, no existe consenso sobre la mejortécnica para obtenerlas.nObjetivo: Evaluar los resultados de las técnicas empleadas paraobtener biopsias en pacientes con sospecha de EICH intestinal. Material y métodos: Estudio retrospectivo que incluye pacientessometidos a alo-TCPH entre 2010 y 2019, con sospecha de EICH intes-tinal estudiados mediante biopsias digestivas: esofagogastroduodenales(endoscopia digestiva alta - EDA) o rectales (colonoscopia o biopsiadirecta). Recogimos variables cuantitativas, expresadas como medianay rango intercuartílico; y cualitativas, expresadas en frecuencia absolutay porcentaje. Resultados: Estudiamos 23 pacientes (60,9% varones). La medianade edad en el momento de la biopsia fue 9 años (7-14 años). EmpleamosEDA en el 47,8% (n= 11), colonoscopia en 26,1% (n= 6) y biopsiadirecta en el 34,8% (n= 8); siendo positivas para EICH en 2 (18,2%), 2(33,3%) y 4 (50%), respectivamente.Conclusiones. Las muestras obtenidas mediante biopsia directase plantean como una alternativa eficiente en el diagnóstico del EICH.(AU)
Introduction: Graft-versus-host disease (GVHD) is a frequentcomplication of allogeneic hematopoietic stem cell transplantation(allo-HSCT), with high morbidity and mortality rates. Intestinalclinical signs are unspecific, which means differential diagnosis withinfections and drug-related etiology should be carried out. Even though intestinal biopsy is widely considered as the gold standardtechnique, there is no consensus as to which sampling method is best. Objective: To assess the results of the biopsy techniques usedin patients with suspected intestinal GVHD.Materials and methods. A retrospective study of patients withsuspected intestinal GVHD undergoing allo-HSCT from 2010 to2019 was carried out. They were assessed through digestive biopsy esophagogastroduodenal biopsy (upper GI endoscopy UGIE)or rectal biopsy (colonoscopy or direct biopsy). Quantitative vari-ables, expressed as median and interquartile range, and qualitativevariables, expressed as absolute frequency and percentage, werecollected. Results:23 patients were studied, 60.9% of whom were male.Median age at biopsy was 9 years (7-14 years). UGIE was used in47.8% of patients (n=11), colonoscopy was used in 26.1% of pa-tients (n=6), and direct biopsy was used in 34.8% of patients (n=8),with GVHD positive results in 2 (18.2%), 2 (33.3%), and 4 (50%)patients, respectively. Conclusions: Samples taken through direct biopsy stand as aneffective alternative in GVHD diagnosis.(AU)
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Humanos , Masculino , Femenino , Preescolar , Niño , Biopsia , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Médula Ósea , Colonoscopía , Cirugía General , Pediatría , Estudios RetrospectivosRESUMEN
We use a relativistic ionization front to provide various initial transverse wakefield amplitudes for the self-modulation of a long proton bunch in plasma. We show experimentally that, with sufficient initial amplitude [≥(4.1±0.4) MV/m], the phase of the modulation along the bunch is reproducible from event to event, with 3%-7% (of 2π) rms variations all along the bunch. The phase is not reproducible for lower initial amplitudes. We observe the transition between these two regimes. Phase reproducibility is essential for deterministic external injection of particles to be accelerated.
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The laser interaction with an electron-positron-ion mixed plasma is studied from the perspective of the associated high-order harmonic generation. For an idealized mixed plasma which is assumed with a sharp plasma-vacuum interface and uniform density distribution, when it is irradiated by a weakly relativistic laser pulse, well-defined signals at harmonics of the plasma frequency in the harmonic spectrum are observed. These characteristic signals are attributed to the inverse two-plasmon decay of the counterpropagating monochromatic plasma waves which are excited by the energetic electrons and the positron beam accelerated by the laser. Particle-in-cell simulations show the signal at twice the plasma frequency can be observed for a pair density as low as â¼10^{-5} of the plasma density. In the self-consistent scenario of pair production by an ultraintense laser striking a solid target, particle-in-cell simulations, which account for quantum electrodynamic effects (photon emission and pair production), show that dense (greater than the relativistically corrected critical density) and hot pair plasmas can be created. The harmonic spectrum shows weak low-order harmonics, indicating a high laser absorption due to quantum electrodynamic effects. The characteristic signals at harmonics of the plasma frequency are absent, because broadband plasma waves are excited due to the high plasma inhomogeneity introduced by the interaction. However, the high-frequency harmonics are enhanced due to the high-frequency modulations from the direct laser coupling with created pair plasmas.
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O objetivo deste estudo foi investigar a interferência do teor de gordura do leite no ponto de congelamento (PC) obtido pelo infravermelho com transformada de Fourier (FTIR). Uma fração de leite cru foi desnatada, obtendo-se creme e leite desnatado. O leite integral e o desnatado foram adicionados com água (0%, 2%, 5%, 10%, 15% e 20%). O leite desnatado remanescente foi adicionado com creme (5%, 10%, 15%, 20%) e água (0%, 2%, 5%, 10%, 15% e 20%). As amostras foram analisadas para PC (crioscópio eletrônico e FTIR) e composição (FTIR). O PC medido por FTIR foi altamente correlacionado com o método do crioscópio eletrônico (acima de 98,5%) e, como esperado, a adição de água foi significativa (P≤0,001) ao aumentar o PC do leite em ambos os métodos. No entanto, o alto teor de gordura no leite cru resultou na redução do PC ao se utilizar o FTIR, enquanto o baixo teor de gordura resultou em aumento do PC (P≤0,001). Uma vez que a adição de água causou o efeito inverso do alto teor de gordura no PC medido por FTIR, é importante considerar o teor de gordura do leite para evitar interpretações erradas do PC quando se utiliza o método FTIR.(AU)
The objective of this study was to investigate the interference of milk fat content upon the Freezing Point (FP) obtained by Fourier-transform infrared (FTIR). A fraction of raw milk was skimmed, obtaining cream and skim milk. Whole and skim milk were added with water (0, 2, 5, 10, 15, and 20%). The remaining skim milk was added with cream (5, 10, 15, 20%) and water (0, 2, 5, 10, 15, and 20%). Samples were analyzed for FP (thermistor cryoscope and FTIR) and composition (FTIR). FP measured by FTIR was highly correlated with the thermistor cryoscope method (above 98.5%) and, as expected, water addition was significant (P≤0.001) upon increasing milk FP in both methods. However, high fat content in raw milk resulted in decreasing FP when using FTIR, while low fat content resulted in increased FP (P≤0.001). Since water addition caused the inverse effect of high fat on FP measured by FTIR, it is important to regard the fat content of milk to avoid misinterpretation of FP when using the FTIR method.(AU)
Asunto(s)
Leche/química , Almacenamiento de Alimentos/métodos , Alimentos Crudos/análisis , Alimentos Congelados/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodosRESUMEN
Raman or Brillouin amplification of a laser beam in plasma has long been seen as a way to reach multi-PW powers in compact laser systems. However, no significant plasma-based Raman amplification of a laser pulse beyond 0.1 TW has been achieved in nearly 20 years, and only one report of Brillouin amplification beyond 1 TW. In this paper, we reveal novel non-linear criteria for the initial seed pulse that will finally open the door to efficient Raman and Brillouin amplification to petawatt powers and Joule-level energies. We show that the triple product of the coupling constant [Formula: see text], seed pulse duration [Formula: see text] and seed pulse amplitude a for the Raman seed pulse (or [Formula: see text] for Brillouin) must exceed a specific minimum threshold for efficient amplification. We also analyze the plasma-based Raman and Brillouin amplification experiments to date, and show that the seed pulses used in nearly all experiments are well below our new threshold, which explains the poor efficiency obtained in them. Finally, we analyze a recent Brillouin amplification experiment that used increased seed pulse power to obtain Joule-level amplification, and find excellent agreement with our theory.
RESUMEN
PURPOSE: Neoadjuvant chemoradiotherapy (nCRT) followed by surgery in patients with resectable esophageal or esophagogastric junctional (GEJ) (Siewert I) cancer is associated with long term overall survival benefits. Up to one third of all patients submitted to nCRT present pathological complete response (pCR). 18F-fluorodeoxyglucose positron emission tomography with CT (18F-FDG PET-CT) is an important tool for assessing treatment response. Purpose was to assess retrospectively the power of 18F-FDG PET-CT in predicting pCR to evaluate the feasibility of a "watch and wait" approach. PATIENTS AND METHODS: Retrospective analysis of a prospective database with esophageal or GEJ submitted to pre-operative chemoradiation. Pre and pos treatment 18F-FDG PET-CT were reviewed and classified using visual assessment and PERCIST criteria and the values of maximum standard uptake value were also recorded. Patients were classified as pCR or non-PCR. 18F-FDG PET-CT and pathological findings were compared against each other. RESULTS: Forty-three patients were included. The median age was 67 years and 90.7% were male. All patients underwent preoperative CRT and were evaluated with 18F-FDG PET-CT pre and post treatment. Transthoracic surgery was performed in all patients. Histological type was adenocarcinoma in 37% and squamous cell carcinoma in 58%. pCR was achieved in 56% of cases. Visual assessment of 18F-FDG PET-CT showed overall sensitivity 57.9%, specificity 62.5% and PERCIST criteria had 100% sensibility and 16.7% specificity. CONCLUSIONS: 18F-FDG PET-CT is not an ideal predictor of pCR but if we use the PERCIST criteria we will have a high sensitivity and negative predictive value, avoiding false negative scans.