RESUMEN
The polar discontinuity at any ferroelectric surface creates a depolarizing field that must be screened for the polarization to be stable. In capacitors, screening is done by the electrodes, while in bare ferroelectric surfaces it is typically accomplished by atmospheric adsorbates. Although chemisorbed species can have even better screening efficiency than conventional electrodes, they are subject to unpredictable environmental fluctuations and, moreover, dominant charged species favor one polarity over the opposite. This paper proposes a new screening concept, namely surface functionalization with resonance-hybrid molecules, which combines the predictability and bipolarity of conventional electrodes with the screening efficiency of adsorbates. Thin films of barium titanate (BaTiO3 ) coated with resonant para-aminobenzoic acid (pABA) display increased coercivity for both signs of ferroelectric polarization irrespective of the molecular layer thickness, thanks to the ability of these molecules to swap between different electronic configurations and adapt their surface charge density to the screening needs of the ferroelectric underneath. Because electron delocalization is only in the vertical direction, unlike conventional metals, chemical electrodes allow writing localized domains of different polarity underneath the same electrode. In addition, hybrid capacitors composed of graphene/pABA/ferroelectric have been made with enhanced coercivity compared to pure graphene-electode capacitors.
RESUMEN
Las enfermedades reumáticas constituyen un grupo de afecciones cuyo mecanismo patogénico se enfoca en la persistencia de un proceso inflamatorio que origina manifestaciones articulares y sistémicas. Aunque no es frecuente, en ocasiones el proceso inflamatorio genera complicaciones graves que requieren intervención quirúrgica como es el caso de la colecistitis aguda. Se presenta el caso de una paciente femenina de 36 años de edad, con diagnóstico de lupus eritematoso sistémico de 5 años de evolución que ingresa con COVID-19 y a los 6 días de hospitalización comienza con un cuadro franco de abdomen agudo que requirió intervención quirúrgica de urgencia. Se presenta el cuadro por la coexistencia de la enfermedad reumática, la infección por COVID-19 y el evento agudo secundario al proceso inflamatorio que causan ambas afecciones(AU)
Rheumatic diseases constitute a group of conditions whose etiopathogenic mechanism focuses on the persistence of an inflammatory process that generates joint and systemic manifestations. Although it is not frequent, sometimes the inflammatory process generates serious complications that require surgical intervention, as is the case with acute cholecystitis. The case of a 36-year-old female patient is presented, with a diagnosis of systemic lupus erythematosus of 5 years of evolution who was admitted due to symptoms compatible with COVID-19 and after 6 days of hospitalization she began with a clear picture of acute abdomen that required emergency surgical intervention. The picture is presented due to the coexistence of rheumatic disease, COVID-19 infection and the acute event secondary to the inflammatory process that both conditions generate(AU)
Asunto(s)
Humanos , Femenino , Adulto , Colecistitis Aguda/cirugía , COVID-19/complicaciones , Abdomen Agudo/cirugíaRESUMEN
Breast reconstruction using contralateral autologous tissue, also known as breast sharing, is a viable option previously described in the literature, whereby flaps based on perforators of the internal mammary artery (internal mammary artery pedicle) are used. We report a postoncological breast reconstruction case using a microvascular flap taken from the lateral pole of the contralateral breast. We highlight the importance of preserving the medial pole of the donor breast for improving cosmesis, avoiding symmastia, and preserving the intermammary sulcus, as a difference with flaps based on the internal mammary artery pedicle flaps. Breast sensation could be recovered by neurotization of the lateral intercostal nerve, which may be included in the contralateral breast flap to be transferred. Contralateral breast free flaps could be an alternative to reconstruct the breast in selected patients. Oncological risk factors are discussed. Advances in genetic testing and tumor cell biology could help us to select the accurate candidates for this reconstructive technique.
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The use of the eHealth has become feasible and acceptable in a variety of fields and contexts in Colombia. This article reports on the Colombian experience using eHealth tools applied to cancer, as well as the challenges, emerging trends, and positive outcomes related to the use of information technology and communication in the national health system. One of these outcomes has been Colombia's National Cancer Information System, in place since 2012, which is the result of political action and strategies focused on applying these innovative technologies in the field of health. The final judgment will depend of the extent to which it is possible to guide timely, effective, and coordinated interventions to optimize care for people with cancer, improve their quality of life, and significantly reduce inequalities. Once this is achieved, the next step should be to replicate the experience and apply eHealth-based tools more broadly in the contexts and fields that the country and the Region require.
Asunto(s)
Informática Médica , Neoplasias , Telemedicina/organización & administración , Colombia , HumanosRESUMEN
El uso de la eSalud es factible y aceptable en muy variados temas y contextos en Colombia. En este artículo se expone la experiencia colombiana en el uso de las herramientas de eSalud aplicadas al cáncer, así como los retos, las tendencias emergentes y los efectos positivos relacionados con el uso de las tecnologías de la información y las comunicaciones en el Sistema Nacional de Salud. Como resultado, en Colombia se cuenta desde 2012 con el Sistema de Información Nacional en Cáncer, resultado de acciones políticas y estrategias dirigidas a aplicar estas novedosas tecnologías en la salud. La valoración final dependerá de la medida en que se logre orientar intervenciones oportunas, eficaces y articuladas para optimizar la atención de las personas con cáncer, mejorar su calidad de vida y reducir significativamente las desigualdades. De lograrse, el siguiente paso debe ser replicar esta experiencia y aplicar las herramientas basadas en eSalud de forma más amplia en los contextos y temas que el país y la Región requieren.
The use of the eHealth has become feasible and acceptable in a variety of fields and contexts in Colombia. This article reports on the Colombian experience using eHealth tools applied to cancer, as well as the challenges, emerging trends, and positive outcomes related to the use of information technology and communication in the national health system. One of these outcomes has been Colombia's National Cancer Information System, in place since 2012, which is the result of political action and strategies focused on applying these innovative technologies in the field of health. The final judgment will depend of the extent to which it is possible to guide timely, effective, and coordinated interventions to optimize care for people with cancer, improve their quality of life, and significantly reduce inequalities. Once this is achieved, the next step should be to replicate the experience and apply eHealth-based tools more broadly in the contexts and fields that the country and the Region require.
Asunto(s)
Humanos , Informática Médica , Neoplasias , Telemedicina/organización & administración , ColombiaRESUMEN
We report on an extremely fast and versatile synthetic approach, based on microwave assisted sol-gel chemistry, that allows a conformal nanometric coating of intricate three-dimensional structures. Using this methodology, we have achieved a conformal coverage of large areas of three-dimensional opals with a superparamagnetic manganese ferrite layer, yielding magneto-photonic crystals with excellent quality. The use of a ternary oxide for the ultrathin coating demonstrates the potential of this methodology to realize three-dimensional structures with complex materials that may find applications beyond photonics, such as energy, sensing or catalysis.
Asunto(s)
Cristalización/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Luz , Sustancias Macromoleculares/química , Magnetismo , Ensayo de Materiales , Conformación Molecular , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
Three-dimensional magnetophotonic crystals (3D-MPCs) are being postulated as appropriate platforms to tailor the magneto-optical spectral response of magnetic materials and to incorporate this functionality in a new generation of optical devices. By infiltrating self-assembled inverse opal structures with monodisperse nickel nanoparticles we have fabricated 3D-MPCs that show a sizable enhancement of the magneto-optical signal at frequencies around the stop-band edges of the photonic crystals. We have established a proper methodology to disentangle the intrinsic magneto-optical spectra from the nonmagnetic optical activity of the 3D-MPCs. The results of the optical and magneto-optical characterization are consistent with a homogeneous magnetic infiltration of the opal structure that gives rise to both a red-shift of the optical bandgap and a modification of the magneto-optical spectral response due to photonic bandgap effects. The results of our investigation demonstrate the potential of 3D-MPCs fabricated following the approach outlined here and offer opportunities to adapt the magneto-optical spectral response at optical frequencies by appropriate design of the opal structure or magnetic field strength.
RESUMEN
We report here on a fast magneto-optical characterization method for colloidal liquid dispersions of magnetic nanoparticles. We have applied our methodology to Ni nanoparticles with size equal or below 15 nm synthesized by a ligand stabilized solution-phase synthesis. We have measured the magnetic circular dichroism (MCD) of colloidal dispersions and found that we can probe the intrinsic magnetic properties within a wide concentration range, from 10(-5) up to 10(-2) M, with sensitivity to concentrations below 1 microg/mL of magnetic Ni particles. We found that the measured MCD signal scales up with the concentration thus providing a means of determining the concentration values of highly diluted dispersions. The methodology presented here exhibits large flexibility and versatility and might be suitable to study either fundamental problems related to properties of nanosize particles including surface related effects which are highly relevant for magnetic colloids in biomedical applications or to be applied to in situ testing and integration in production lines.
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Coloides/química , Nanopartículas del Metal/química , Níquel/química , Dicroismo Circular , Magnetismo , NanotecnologíaRESUMEN
Se hizo un estudio descriptivo con el objeto de analizar el manejo de la enfermedad de Paget en el Instituto Nacional de Cancerolog1a en el periodo de 1939 a 1999. Se revisaron las historias clínicas de todas las pacientes con Enfermedad de Paget que ingresaron al INC durante este periodo, 94 en total, de las que se excluyeron 2 por falta de confirmación histológica. El promedio de edad fue de 56 años, con rangos de 30 a 60 años, de los factores de riesgo analizados para la recaida fueron significativos solamente el tipo de tratamiento inicial (cirugía o no cirugía), presencia de masa y ganglios comprometidos, se realizo vaciamiento a 36 pacientes, el compromiso ganglionar fue del 52 por ciento (19 pacientes),el promedio de sobrevida sin la presencia de masa subyacente fue del 95 por ciento a 5 años y con masa de 67 por ciento a cinco años. La sobrevida se afectó por la presencia de masa (p igual 0.02) y las metástasis ganglionares (p menor 0.001), sin encontrar diferencia de sobrevida con los distintos tipos histológicos. En el INC durante 60 años se han instaurado múltiples tratamientos para la enfermedad de Paget, el que aportó mejores resultados fue la cirugía.
Asunto(s)
Neoplasias de la Mama , Cirugía General , Enfermedad de Paget Mamaria , Mastectomía , PezonesRESUMEN
Primary angiosarcoma of the breast represent 0.04 per cent of the malignant neoplasm of the gland and is considered the more aggressive and lethal. Its biological behavior is related to sixe and histologic grade. There are no prospective studies that allow conclusions about the utility of chemo-radiotherapy adjuvant treatment; mastectomy is the best therapy
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Humanos , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/etiología , Hemangiosarcoma/diagnóstico , Hemangiosarcoma/etiología , Hemangiosarcoma/fisiopatologíaRESUMEN
Se estudiaron 20 niños recién nacidos, hijos de madres consumidoras de pasta base de coca (basuco), en comparación con 19 controles nacidos de madres no consumidoras, con el fin de detectar en los primeros alteraciones neurológicas y evidencias de supresión; se hallaron las siguientes con frecuencias significativamente mayores en los hijos de madres consumidoras: temblor (p: 0.00001), irritabilidad (p: 0.0015), náuseas (p: 0.003), llanto deprimido (p: 0.004) y succión deprimida (p:0.02); en los restantes signos de supresión (vómito, anorexia, hipersomnia, hiposomnia, hipertonía, cólico y diarrea) y alteraciones neurológicas
Twenty newborn infants from mothers that consumed coca leaves' paste during pregnancy were compared with 19 controls as to their neurological behavior and supression evidences; the following alterations were significantly more frequent (p < 0.05) in infants from consumer mothers: Tremor, irritability, nausea, and depression of crying, suction and prension. The duration of these alterations as well as that of other neurological abnormalities was significantly longer in infants from consumer mothers. These findings reveal that neonates exposed to cocaine because their mothers consumed coca leaves' paste during pregnancy, reveal neurologic alterations as well as suppression signs that sugest a direct and lasting effect of the drug on their central nervous systems; these infants constitute a serious public health problem whose management requires decision and solid knowledge on its repercusions
Asunto(s)
Trastornos Relacionados con Sustancias , Cocaína , Síndrome de Abstinencia NeonatalRESUMEN
Se estudiaron los hijos de 25 adolescentes extremas (13-15 años), 77 intermedias (16-17 años), 88 limítrofes (18-19 años) y 100 controles mayores (20-30 años). Los hijos de las extremas tuvieron mayores porcentajes de morbilidad, lo mismo que los hijos de todas las adolescentes en comparación con los de las controles (p < 0.05). Entre la morbilidad resaltó el mayor grado de asfixia perinatal en los hijos de las adolescentes extremas las limítrofes. El peso, la talla, el perímetro cefálico y el índice de Rohrer fueron similares en los cuatro grupos. No se detectó asociación entre la morbilidad de los niños y las siguientes variables maternas: El estado civil, la morbilidad y el rechazo al embarazo. La mortalidad global de los hijos de las adolescentes fue significativamente mayor que la de los controles, pero a costa de los hijos de las intermedias {p < 0.05). En conclusión, tanto la morbilidad general como la mortalidad son superiores entre los hijos de las adolescentes más jóvenes.
Morbidity was studied in neonate infants of 25 young adolescent mothers (13 to 15 year-old), 77 mid adolescent mothers (16 to 17 year old), 88 borderline adolescent mothers (18 to 19 year-old) and 100 post adolescent ones (20 to 30 year old). Young adolescents' children as well as children from all adolescent mothers showed higher morbidity rates as compared to those of controls (p < 0.05). A higher frequency of perinatal asphyxia in neonates of both young and borderline adolescents was evident. Weight, height, cephalic perimeter and Rohrer index were similar in the four groups. No correlation was observed between neonates' morbidity and the following maternal variables: marital status, morbidity and pregnancy rejection. Overall mortality of adolescents' children, particularly of those of mid adolescent mothers, was significantly higher than that of controls (p < 0.05}. In conclusion, and inverse correlation was found between neonates' overall morbidity and mortality and the age of the adolescent mothers.
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Embarazo , Morbilidad , AdolescenteRESUMEN
Se revisaron 159 pacientes de sexo femenino con trasplante renal en la Unidad Renal del Hospital U. San Vicente de Paul, en un periodo que va desde agosto de 1973 hasta junio de 1987, con el fin de evaluar la frecuencia y el pronostico del embarazo. Se presentaron siete embarazos en seis mujeres de 76 candidatas potenciales, cuyos resultados fueron asi: tres operaciones cesareas a causa de ruptura precoz de las membranas, un parto vaginal y tres abortos. Una paciente presento rechazo del injerto durante el tercer trimestre del embarazo. La inmunoterapia no tuvo ningun efecto deletereo sobre los fetos. Aunque el numero de pacientes es pequeno para sacar conclusiones definitivas, se puede afirmar que no hubo aumento del riesgo sobre el injerto en aquellas pacientes embarazadas con funcion renal estable despues del injerto renal
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Embarazo , Humanos , Femenino , Trasplante de Riñón , ColombiaRESUMEN
Con la metodologia de cohortes se estudiaron 23 parejas madre-hijo consumidores de basuco; (cohorte expuesta) y 20 parejas no consumidoras que sirvieron como controles. Se comparo en los ninos la frecuencia de retardo ponderal, alteraciones neurologicas, alteraciones fisiologicas en el higado, los rinones y la sangre y signos clinicos, hematologicos y oseos de plumbismo; se determinaron los niveles de plomo en la sangre materna y en la del cordon umbilical. Se encontro que los ninos expuestos presentaban retardo generalizado del crecimiento, incluyendo el tamano del cerebro, y un cuadro neurologico caracterizado por: llanto deprimido, irritabilidad, nauseas y disminucion de los reflejos de succion, marcha automatica, enderazamiento y del alpinista. Con respecto a los tres ultimos, aunque su frecuencia absoluta no fue significativamente superior, si lo fue la duracion promedio de la depresion. Las concentraciones sanguineas de plomo en las parejas expuestas fueron: 15.2+-5.8 ug/dl en las madres. En los controles se encontraron 6.8+-5.0 y 8.4+-4.5 ug/dl respectivamente. Se detectaron alteraciones oseas en 15 ninos expuestos (75%), a saber: en 14 retardo de la maduracion relacionado, posiblemente con el bajo peso y en 6 (30%), lesiones radiodensas metalisiarias longitudinales o transversales atribuibles al deposito de plomo. No se detectaron signos clinicos de plumbismo ni alteraciones fisiologicas en los rinones, el higado o la sangre durante el tiempo del estudio. Los anteriores hallazgos permiten concluir que la exposicion del feto al basuco consumido
We performed a cohort study, to investigate the effects of maternal basuco consumption on fetuses and newborn infants; the exposed cohort consisted of a group of 23 addict pregnant women; the control cohort was constituted by 20 non-addict, non-smoking pregnant women; newborn infants of both groups were checked to detect general and brain growth retardation, neurological abnormalities, and alterations of liver and kidney functions; blood lead concentrations were measured in the mothers and infants. In the exposed infants we found retardation of general and brain growth; neurological involvement evidenced by irritability, nausea and weak cry; also by depression of the sucking, stepping response, Landau and placing reflexes (in the latter three, duration of the depression but not its frequency was significantly higher in the exposed infants); bone changes consisting of maturation delay and metaphyseal dense streaks attributable to lead deposition. Despite significantly higher blood-lead levels in the exposed mothers and infants no evidence could be found of liver, kidney or hematological alterations; lead-poisoning signs were absent. Based on these findings we conclude that fetal exposure to basuco is associated with high blood lead. Levels, generalized growth retardation which includes the brain, bone lesions and a clear-cut but self-limited neurological syndrome
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Humanos , Masculino , Femenino , Embarazo , Recién Nacido , Trastornos Relacionados con Sustancias , Retardo del Crecimiento Fetal/epidemiología , Cocaína , Colombia , Trastornos Relacionados con Sustancias/clasificación , Trastornos Relacionados con Sustancias/complicaciones , Trastornos Relacionados con Sustancias/epidemiología , Plomo/efectos adversos , Plomo/sangre , Cocaína/efectos adversos , Cocaína/análogos & derivados , Cocaína/sangreRESUMEN
La obtencion del clorhidrato de cocaina a partir de la hoja de coca requiere el uso de gasolina; residuos de esta pueden permanecer en la pasta base(basuca); al fumar esta, mezclada con cigarrillo o marihuana (basuco) el consumidor puede captar residuos de plomo e incrementar sus concentraciones sanguineas del mismo; quisimos saber si el uso del basuco durante el embarazo podria tener tal efecto en los recien nacidos de madres consumidoras. Se midieron las concentraciones de plomo serico en 19 recien nacidos hijos de gestantes consumidoras de basuco y en 18 de sus madres, asi como en 20 parturientas no consumidoras y en 19 de sus hijos. Se utilizo un espectrofotometro de absorcion atomica Perkin-Elmer modelo 2380. Las madres se dividieron en 4 grupos segun el grado de consumo, asi: leve, moderado, intenso y ninguno. Las cifras promedio y las DE encontradas fueron respectivamente: en los hijos:13.5 mas o menos 9.4; 15.8 mas o menos 6.5; 16.6 mas o menos 7.8; 6.9 mas o menos 5.0 ug/dl, y en las madres, 13.3 mas o menos 4.6; 13.5 mas o menos 6.9; 16.2 mas o menos 4.9; 8.4 mas o menos 4.6 ug/dl. Las pruebas estadisticas demostraron diferencias altamente significativas entre las madres e hijos expuestos al basuco y la cohorte no expuesta; no existio diferencia entre las concentraciones segun el grado de consumo. Los altos niveles de plomo detectados ameritan seguimiento de los recien nacidos y estudios adicionales, con el fin de evaluar su repercusion a largo plazo
Obtention of cocaine clorhydrate from coca leaves requires the use of gasoline; therefore residues such as lead may remain in the base paste (basuca); the latter is smoked, under the name basuco, mixed with tobacco or marijuana; It is conceivable that the smoker takes up lead residues that Increase lead blood levels; we wanted to determine whether the use of basuco during pregnancy could produce such effect In the newborninfant. Serum lead concentrations were measured In 19 newborn children and In 18 of their mothers. The latter were basuco consumers. They were compared to those of 20 non consuming delivering women along with 19 of their newborn Infants. Measurements were performed on a Perkin-Palmer model 2380 atomic absorptionspectrophotometer. Women were divided in four groups according to the degree of consumption, as follows: mild, moderate, Intense or non existent. Mean levels and SDs in the children were respectively: 13.5 ± 9.4; 15.8 ± 6.5; 16.6 ± 7.8; 6.9 ± 5.0 ug/dl; and In their mothers: 13.3 ± 4.6; 13.5 ± 6.9; 16.2 ± 4.9; 8.4 ± 4.6 ug/dl Statistic analysis revealed highly significant differences between mothers and children exposed to basuco and those that were not exposed. No difference was observed ac. cording to the degree of consumption. In conclusion: newborn from basuco consuming mothers have Increased lead blood levels; the long term effects of such alteration should be the subject of further studies