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Resumen Las porfirias son errores congénitos poco frecuentes del metabolismo de las porfirinas. La porfiria cutánea tardía (PCT) es la más frecuente dentro de este grupo de enfermedades. Reportamos el estudio evolutivo de metabolitos porfirínicos de una paciente de 51 años con porfiria cutánea tardía, cuatro años después de su diagnóstico. Durante este período, se le indicó un esquema terapéutico de flebotomías en el Instituto de Hematología e Inmunología. Uno de los exámenes complementarios para su seguimiento fue la determinación de porfirinas totales en la orina, plasma y heces. Los resultados del estudio bioquímico de las porfirinas mostraron mejoría en todos los parámetros, lo que contribuyó a corroborar la utilidad del estudio de estos metabolitos como seguimiento de esta enfermedad y efectividad del tratamiento. Abstract Porphyrias are rare congenital errors in the metabolism of porphyrins. Porphyria cutanea tarda is the most frequent among different types of porphyrias. We report the follow-up study of porphyrin metabolites of a 51-year-old patient with porphyria cutanea tarda four years later of her diagnosis. During this period, it was indicated a therapeutic scheme of phlebotomies in the Institute of Hematology and Immunology. One of the complementary examinations for its follow-up was the determination of total porphyrins in the urine, plasma and feces. Porphyrins in plasma decreased from 13 500 nmol/L at onset of disease to 250 nmol/L four years later. Although, porphyrins in feces and plasma could not quantify, we observed non-presence of peaks at 405 nm and 615.1 nm, respectively. These results contributed to corroborate the usefulness of the study of these metabolites for monitoring of this disease and effectiveness of the treatment.

The freshwater green microalga Haematococcus pluvialis is the richest source of natural astaxanthin. Astaxanthin is a high-value red carotenoid pigment commonly used in the food, feed and cosmetics industries due to its well-known antioxidant, anti-inflammatory and antitumour properties. This study assesses the environmental impacts associated with the production of natural astaxanthin from H. pluvialis at both lab and pilot scale. Closed airlift photobioreactors with artificial illumination, typically used for the production of high-value products to avoid contamination risks and allow controlled lighting conditions, were considered. The study extends from the production of the different inputs to the system to microalgal production, harvesting and further extraction of the carotenoid. The life cycle assessment was performed following the ISO 14040 and ten impact categories were considered in the study: abiotic depletion, acidification, eutrophication, global warming, ozone layer depletion, human toxicity, freshwater aquatic ecotoxicity, marine aquatic ecotoxicity, terrestrial ecotoxicity and photochemical oxidant formation.According to the results, electricity requirements represented the major contributor to the environmental burdens among the activities involved in the production of astaxanthin. For the lab-scale process, the air supply and the production of chemicals and lab materials were also significant contributors in several categories. In the pilot-scale production, the relative environmental impacts were greatly reduced, partially due to changes implemented in the system as a result of lab-scale environmental assessment. However, the production of electricity still dominated the impacts in all categories, particularly due to the cultivation stage. For this reason, a sensitivity assessment was proposed in order to identify alternative photobioreactor configurations for astaxanthin production. Two of the evaluated options, based on the use of sunlight instead of artificial illumination, presented significant reductions of impact. However, the improvements observed in these cases were limited by the decrease in biomass productivity associated with sunlight culture systems. Therefore, a two flat-panel photobioreactor system with artificial illumination is proposed as a suitable option, allowing reductions between 62% and 79% of the impact depending on the considered category.

This paper presents a procedure to extend the methods of moments in time domain for the transient analysis of thin-wire antennas to include those cases where the antennas are located over a lossy half-space. This extended technique is based on the reflection coefficient (RC) approach, which approximates the fields incident on the ground interface as plane waves and calculates the time domain RC using the inverse Fourier transform of Fresnel equations. The implementation presented in this paper uses general expressions for the RC which extend its range of applicability to lossy grounds, and is proven to be accurate and fast for antennas located not too near to the ground. The resulting general purpose procedure, able to treat arbitrarily oriented thin-wire antennas, is appropriate for all kind of half-spaces, including lossy cases, and it has turned out to be as computationally fast solving the problem of an arbitrary ground as dealing with a perfect electric conductor ground plane. Results show a numerical validation of the method for different half-spaces, paying special attention to the influence of the antenna to ground distance in the accuracy of the results.

Este artículo revisa la relación entre la trama principal y la línea argumental secundaria en la comedia calderoniana “Casa con dos puertas, mala es de guardar”. Se centra en la imbricación de la historia central, los amores de los protagonistas, Marcela y Lisardo, y la relación sentimental de Laura y Félix, que se da en un segundo plano. El autor llega a la conclusión de que la línea de acción secundaria tiene una estructura dramática más compleja que la primera. Destaca así el desarrollo más dinámico de esta trama, la presencia de más elementos de ambigüedad y contradicción en el comportamiento de los personajes, la mayor complejidad del enredo producido por los celos, y, por último, un mayor número de expectativas dramáticas. González García vincula la riqueza constructiva de la pieza, en la que lo secundario pasa a ocupar el primer plano, con uno de los rasgos centrales de la estética manierista, el descentramiento del motivo principal.

Se propone la síntesis de N-Carboximetil-D,L-Treonina (H2 CMT=H1 L) por condensación de D,L-treoninato y cloroacetato potásicos, desalinización parcial en medio neutro y posterior cambio iónico por resina catiónica en forma ácida. Rendimiento: 75%. El tratamiento mediante el programa HYPERQUAD de 238 datos potenciométricos de tres valoraciones de H2 CMT frente a KOH en KNO, O.IM a 25.00±0.05 oC y atmósfera inerte (N2 ) permite la determinación de las constantes de formación de sus especies protonadas, con las que se simula la curva de valoración. En estado sólido, el aminodiácido se caracteriza por su espectro IR y por análisis ténnico (TG-A TD)., N-Carboxymethyl-D,L-threonine (H2 CMT=H2 L) was obtained by reaction of D,L threonine and chloroacetate in alkaline medium and followed by cation change with Amberlite IR-120(H) of the desalinized mother liquor. Yield: 75%. The treatment of 238 potentiometric data from three mixed solutions (H2 L +HCI) by HYPERQUAD program gives to log ,,=8.73(01), log 1 2 =1 1.22(01) and log 1.1=12.76(02) for the species HL-, H2 L and H. 1L' at 298°K, I=O.IM (KNO.1) and N2 inert atmosfere. These constants give a good simulation of the H2 L titration curve. The infrared spectra and TG-DT A data of H2 CMT are al so discussed on the basis of its zwitterionic structure.

Nota de la Redacción: El presente trabajo, aparecido en el tomo XXXII de nuestra revista, contenía numerosas erratas que, en parte, afectaban a las fórmulas. En vez de publicar una «Fe de Erratas» que resultaría farragosa hemos preferido reproducirlo, debidamente corregido. Así queda salvada la seriedad de ARS PHARMACEUTlCA, al tiempo que esperamos haber complacido a los Autores., El ácido N,N' -bis (carboximetil)-meso-djenkólico CH2[SCH2CH(COO") NH2(COOH)]2 monohidrato (H4L.HP) y su clorhidrato (H4L.HCL) se aislan con bajo rendimiento ({5%) de la condensación entre mesodjenkolato y bromoacetato potásicos por cambio cationico con Amberlita IR-120(H). Datos potenciométricos de H4L.HCl+HCl tratados por el programa SUPERQUAD conducen a 10gB" = 8.90, logB'2 = 17.09, logB'3 = 12.57 Y logB'4 = 21.45 para 1 = O.IM (KN03) y 298K. Los grupos formalmente equivalentes de H4L se disocian como poco (pK4-pK3 = 0.71) o nada (pK2 - pK, = 0.60) interactuantes. Los espectros l H.RMN conftrman el esqueleto molecular de los productos obtenidos que, en estado sólido, se carazterizan por sus espectros IR y por TG-ATD.H4L.Hp pierde agua entre 60 y 150 ºC., N,N' -bis( carboxymethyl)-meso-djenkolic acid,CH2[SCH2CH(COO") NH/COOH)]2 ' monohydrate (H4L.HP) ant ist monohydrochloride (H4L.HCl) were obtained from the reaction bettwen meso-djenkolate and bromoacetate (molar ratio 1:2) by cation change with Amberlite IR-l 20 (H). Yield was very low (:5:5%). Potentiometric data of mixed H4L.HCl+HCl solutions teatred by SUPERQUAD program give 10gBII = 8.90, logB'2 = 17.09, 10gB13 = 19.57 Y logB'4 = 21.45 at 298K and I=O.lM (KN03 ). The macrodissociation of te fonnally equivalent groups of H4L occour as wearly (pK4-pK3 = 0.71) or non (pk2-pK, = 0.60) interacting ones. 1H-RMN, IR spectra and TG-DTA data of (H4LH20) and H4L.HCl are discused.