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Ligaria cuneifolia (R. et P.) Tiegh (Loranthaceae) es una hemiparásita sudamericana que produce polifenoles con actividad hipolipemiante, citostática, inmunomoduladora, antioxidante y antimicrobiana. Nuestro objetivo fue determinar el perfil de polifenoles de ejemplares silvestres en distintos órganos y extractos, así como las condiciones más adecuadas para iniciar sus cultivos in vitro. Para el estudio fitoquímico se realizaron cromatografías en capa delgada de tipo monodimensional observándose la presencia de flavonoides, derivados hidroxicinámicos y proantocianidinas en los extractos de hojas, tallos primarios, tallos secundarios y flores. En cuanto al análisis cuantitativo se observaron altos valores de flavonoides en hojas (2,14 mg eq. de rutina por gramo de material seco) y de proantocianidinas en flores (7,52 mg eq. de catequina por gramo de material seco), compuestos responsables de las actividades biológicas mencionadas. Para la iniciación de cultivos in vitro se estudiaron diferentes aspectos: protocolo de desinfección, explanto de iniciación (hojas, pedicelos, frutos, tallos, meristemas y haustorios) y medios de cultivo base (reguladores de crecimiento y agentes antioxidantes). Los tratamientos más efectivos fueron HgCl2 0,05 - 0,2 % en una proporción de 25 explantos cada 100 ml de solución desinfectante y ácido cítrico 2,6 mM o L-cisteína 100 µM como antioxidantes. Solamente fue posible iniciar callos a partir de haustorios cultivados en medio Gamborg B5 con el agregado de ácido 2,4-dicloro-fenoxiacético 2,25 µM como regulador de crecimiento. (AU)

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ABSTRACT Viola maculata Cav., Violaceae, grows in the underwood along the Los Andes mountain system from Neuquén to Tierra del Fuego and Islas Malvinas. It is also known as violeta amarilla or as pilundeu, and is used in popular medicine by the Mapuches as stimulant, in dermatology, and as a lavage in eye diseases. The aim of this work is to examine the morpho-anatomical traits of the leaves and petiole of V. maculata (collected at Parque Nacional Los Alerces, Patagonia, Argentina). Cross sections and scanning electron microscopy of leaves blade and petiole showed a simple organization with simple unicellular trichomes and cells containing tannins, and crystals of calcium oxalate mainly in the spongy parenchyma. As V. maculata is used in traditional medicine, the specification of the anatomical characters is relevant to describe the species.

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This study describes the optimization and validation of a quick and simple method for the simultaneous determination of total content and available fractions of As, Cr, Cu, Ni, Pb and Tl in sediments by ET AAS, which has been proved to be useful for environmental research. The optimization was carried out using a 3(3) Box-Behnken factorial design which was applied to matrices of total digestion and to stages 1 and 2 of the modified BCR sequential extraction scheme for sediments in order to determine the appropriate atomization temperatures and masses for the chemical modifiers: Pd(NO(3))(2) and Mg(NO(3))(2). The simultaneous determination of the elements in all matrices considered was performed, without the use of chemical modifiers at atomization temperatures of 1700 °C for Cd and Tl, and 2100 °C for As, Cu, Cr, Ni and Pb, using a standard calibration curve for calibration purposes. The characteristic masses and limits of detection obtained were 36.5, 1.8, 6.5, 28, 34, 46.5 and 48 ρg and 0.11, 0.001, 0.022, 0.04, 0.2, 0.03 and 0.003 µg g(-1) for As, Cd, Cr, Cu, Ni, Pb and Tl, respectively. The analytical procedure was validated by analyzing three sediment certified reference materials (CRM NCS DC 73315 and LKSD-4 for total content and BCR 701 for available fractions). Good accuracy was obtained (tested statistically, P=0.05, and shown by the high recovery for each element in each matrix), except for total As in the matrix of total digestion, where losses of the analyte could be attributed to sample treatment with HNO(3). The precision of the procedure was between 0.6% and 6%.

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In vitro cultures of Berberis buxifolia were established using thidiazuron (4.5, 23 and 45 mM) or picloram (4 and 40 mM) as plant growth regulators for sustaining growth. For producing berberine, a two-stage culture was performed. In the first step, thidiazuron or picloram were used for biomass production followed by the production stage where benzylaminopurine (4.4 mM) was added as a plant growth regulator. Berberine yields (102 mg g(-1) DW) and in vitro shoot cultures (200 mg g(-1) DW) were significantly lower than those of whole plants in the field (416 mg g(-1) DW). The highest productivity (0.18 mg 1(-1) day(-1)) was attained using picloram (either 4 on 40 mM) in the first stage for producing biomass.

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Introducción. La biopsia aspirativa con aguja fina permite el diagnóstico de enfermedades tan graves como el cáncer en la infancia, en un breve período de tiempo y con gran exactitud. El método se ha establecido como una técnica rápida, efectiva y económica en la biopsia de tumores de cavidades como la abdominal y la torácica. El objetivo de esta investigación fue comprobar la aplicación y validez del método diagnóstico en los tumores intratorácicos e intraabdominales en la infancia. Métodos. En el Hospital Pediátrico «William Soler¼, se realizó un estudio retrospectivo de las citologías aspirativas realizadas en tumores intratorácicos e intraabdominales entre enero de 1999 y diciembre de 2005. En todas se realizó la técnica de biopsia por aspiración preconizada en Estocolmo y se utilizó también la técnica de citopunción. Resultados. El abdomen fue la región más frecuente, en particular, el riñón. Veinte citologías fueron negativas de malignidad (17,6 por ciento) y 65, positivas (57,5 por ciento). Existió una buena correlación citohistológica positiva. La sensibilidad fue del 96,1 por ciento; el valor predictivo positivo, del 94,9 por ciento y la eficiencia, del 92,8 por ciento. Conclusiones. La biopsia con aguja fina es un método eficaz para el diagnóstico de los tumores intraabdominales e intratorácicos en la infancia. Tiene gran valor diagnóstico para cirujanos, pediatras y oncólogos, y permite planificar de manera eficaz la conducta ulterior ante cada paciente(AU)

Introduction. Fine needle aspiration biopsy allows the diagnosis of diseases as severe as cancer in childhood in a short period of time, and with great accuracy. This method has been established as a rapid, effective and economic technique in the biopsy of tumours of cavities such as the abdominal and the thoracic. The objective of this research was to check the application and validity of the diagnostic method in intrathoracic and intraabdominal tumours in children. Methods: A retrospective study of the aspiration cytologies performed in intrathoracic and intraabdominal tumours at William Soler Teaching Children Hospital from January 1999 to December 2005 was conducted . In all of them the aspiration biopsy technique recommended in Stockholm was used, and the cytopuncture technique was also applied. Results. The abdomen was the most frequent region and, in particular, the kidney. Twenty cytologies yielded negative (17.6 percent), and 65 positive (57.5 percent). There was a good positive cytohistologic correlation. Sensivity was 96.1 percent; positive predictive value, 94.9 percent; and efficiency, 92.8 percent. Conclusions. Fine needle biopsy is an effective method for the diagnosis of intraabdominal and intrathoracic tumours in children. It has a great diagnostic value for surgeons, pediatricians and oncologists, and it also allows to plan in a efficient way the conduct to be followed with each patient(AU)

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Introducción. La biopsia aspirativa con aguja fina permite el diagnóstico de enfermedades tan graves como el cáncer en la infancia, en un breve período de tiempo y con gran exactitud. El método se ha establecido como una técnica rápida, efectiva y económica en la biopsia de tumores de cavidades como la abdominal y la torácica. El objetivo de esta investigación fue comprobar la aplicación y validez del método diagnóstico en los tumores intratorácicos e intraabdominales en la infancia. Métodos. En el Hospital Pediátrico ®William Soler¼, se realizó un estudio retrospectivo de las citologías aspirativas realizadas en tumores intratorácicos e intraabdominales entre enero de 1999 y diciembre de 2005. En todas se realizó la técnica de biopsia por aspiración preconizada en Estocolmo y se utilizó también la técnica de citopunción. Resultados. El abdomen fue la región más frecuente, en particular, el riñón. Veinte citologías fueron negativas de malignidad (17,6 por ciento) y 65, positivas (57,5 por ciento). Existió una buena correlación citohistológica positiva. La sensibilidad fue del 96,1 por ciento; el valor predictivo positivo, del 94,9 por ciento y la eficiencia, del 92,8 por ciento. Conclusiones. La biopsia con aguja fina es un método eficaz para el diagnóstico de los tumores intraabdominales e intratorácicos en la infancia. Tiene gran valor diagnóstico para cirujanos, pediatras y oncólogos, y permite planificar de manera eficaz la conducta ulterior ante cada paciente.

Introduction. Fine needle aspiration biopsy allows the diagnosis of diseases as severe as cancer in childhood in a short period of time, and with great accuracy. This method has been established as a rapid, effective and economic technique in the biopsy of tumours of cavities such as the abdominal and the thoracic. The objective of this research was to check the application and validity of the diagnostic method in intrathoracic and intraabdominal tumours in children. Methods: A retrospective study of the aspiration cytologies performed in intrathoracic and intraabdominal tumours at William Soler Teaching Children Hospital from January 1999 to December 2005 was conducted . In all of them the aspiration biopsy technique recommended in Stockholm was used, and the cytopuncture technique was also applied. Results. The abdomen was the most frequent region and, in particular, the kidney. Twenty cytologies yielded negative (17.6 percent), and 65 positive (57.5 percent). There was a good positive cytohistologic correlation. Sensivity was 96.1 percent; positive predictive value, 94.9 percent; and efficiency, 92.8 percent. Conclusions. Fine needle biopsy is an effective method for the diagnosis of intraabdominal and intrathoracic tumours in children. It has a great diagnostic value for surgeons, pediatricians and oncologists, and it also allows to plan in a efficient way the conduct to be followed with each patient.

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Hairy roots of Brugmansia candida produce the tropane alkaloids scopolamine and hyoscyamine. In an attempt to divert the carbon flux from competing pathways and thus enhance productivity, the polyamine biosynthesis inhibitors cyclohexylamine (CHA) and methylglyoxal-bis-guanylhydrazone (MGBG) and the phenylalanine-ammonia-lyase inhibitor cinnamic acid were used. CHA decreased the specific productivity of both alkaloids but increased significantly the release of scopolamine (approx 500%) when it was added in the mid-exponential phase. However, when CHA was added for only 48 h during the exponential phase, the specific productivity of both alkaloids increased (approx 200%), favoring scopolamine. Treatment with MGBG was detrimental to growth but promoted release into the medium of both alkaloids. However, when it was added for 48 h during the exponential phase, MGBG increased the specific productivity (approx 200%) and release (250- 1800%) of both alkaloids. Cinnamic acid alone also favored release but not specific productivity. When a combination of CHA or MGBG with cinnamic acid was used, the results obtained were approximately the same as with each polyamine biosynthesis inhibitor alone, although to a lesser extent. Regarding root morphology, CHA inhibited growth of primary roots and ramification. However, it had a positive effect on elongation of lateral roots.

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The simultaneous multielement determination of Pb, Sn, Ni and Cu in aluminium alloys by electrothermal atomic absorption spectrometry (ETAAS) was performed by a quick method using slurry sampling. The metallic colloidal slurries were obtained by an electrical discharge operated in liquid medium. In this work, the effects of aluminium were evaluated and the results show that it causes a strong retention of Pb, Ni and Cu at low pyrolysis temperatures which is overcome by employing high pyrolysis temperatures. Aluminium also significantly improves the thermal stabilisation of Pb and Sn, it being possible to reach pyrolysis temperatures of 1100 and 1300 degrees C, respectively. Such stabilisation indicates that the performance of aluminium as a matrix modifier for Pb is better than that obtained using phosphate and magnesium nitrate without substantial changes of the figures of merit. The effects of aluminium on the atomisation characteristics of the elements and those coming from the simultaneous multielement determination on the figures of merit of the elements are also discussed. In this work, a calibration procedure involving a matrix matching method with aqueous aluminium standards is proposed as a simple and efficient way to solve the inconveniences originated by the aluminium matrix. The proposed method was applied to the simultaneous multielement determination of several aluminium-base alloy standards giving results well within the recommended values.