Micropropagación de plantas de lechosa en recipientes de inmersión temporal a partir de brotes axilares Micropropagation of papaya plants in temporary immersion recipients from axilary shoots

Título en ingles: Micropropagation of papaya plants in temporary immersion recipients from axilary shootsTítulo corto: Micropropagación de lechosa en recipientes de inmersión temporal.Resumen: Se estandarizaron las condiciones de iniciación, multiplicación, enraizamiento y aclimatización de plantas hermafroditas de lechosa cv Maradol provenientes de brotes axilares, producidos en recipientes de inmersión temporal RITA®. En cada envase, contentivo de 200 ml de medio de cultivo líquido de Fitch, se colocaron cuatro brotes de 2 a 3 cm de longitud. Los biorreactores se conectaron a tres líneas de inmersión de 5, 2 y 1 min cada 4h y se colocaron 6 envases en promedio por línea, en condiciones de fotoperíodo de 16 h. Transcurridos 30 a 45 días, se cuantificaron los brotes y se clasificaron de acuerdo al tamaño: 2 cm (pequeños), entre 2 a 3 cm (medianos),  ˃ 3 cm con y sin raíz (grandes). Los dos primeros tipos de brotes se continuaron multiplicando en los mismos medios; y los más elongados se aclimatizaron utilizando el Sistema Autotrófico Hidropónico (SAH). Se determinó la sanidad y la fidelidad de las plantas producidas mediante pruebas de ELISA y RAPD, respectivamente. Durante un periodo de 6 meses se reciclaron un total de 47 recipientes, los cuales produjeron 1.091 brotes: 377  pequeños; 482 medianos; 175 grandes sin raíz y 57 con raíz. Usando el SAH se obtuvo 89,5% de plantas aclimatizadas cuando se usaron brotes enraizados, y 41,6% a partir de brotes sin  raíces. Con la combinación de las técnicas RITA y SAH se logró un sistema continuo y eficiente de producción de plantas sanas y fieles al tipo, en comparación con los métodos convencionales de micropropagación y aclimatización.Palabras clave: Carica papaya, RITA®, sistema autotrófico, estabilidad genética.Key words: Carica papaya, RITA®, autotrophic system, genetic stability.Recibido: mayo 16 de 2014   Aprobado: abril 21 de 2015We standardized initiation, multiplication, rooting and acclimatization conditions of papaya cv Maradol hermaphrodite plants from axillary buds produced in temporary immersion reactor RITA®. Recipients contained 200 ml of Fitch liquid culture medium, and four shoots of 2 to 3 cm. in length were placed in each. The bioreactors were connected to three different immersion lines of 5, 2, and 1 min each 4h, with 6 containers per line on average, in 16 h photoperiod. After 30 to 45 days, the shoots produced were quantified and classified according to size: 2 cm (small), from 2 to 3 cm (medium), 3 cm with or without roots (large). The first two types of shoots were multiplied in the same culture media, and more elongated shoots were acclimatized using Autotrophic Hydroponic System (AHS). The sanity and fidelity of the produced plants were determined using ELISA and RAPD, respectively. For a period of six months 47 vessels were recycled and 1,091 shoots were produced: 377 small; 482 medium; 175 large without roots and 57 rooted shoots. Using AHS, 89.5% acclimatized plants were obtained when rooted shoots were used, and 41.6% from rootless shoots. With the combination of RITA and AHS techniques we achieved a continuous and efficient production of healthy and true to type papaya plants, in comparison to conventional micropropagation and acclimatization procedures.Key words: Carica papaya, RITA®, autotrophic system, genetic stability

Receptor-Based Virtual Screening and Biological Characterization of Human Apurinic/Apyrimidinic Endonuclease (Ape1) Inhibitors

The endonucleolytic activity of human apurinic/apyrimidinic endonuclease (AP endo, Ape1) is a major factor in maintaining the integrity of the genome. Conversely, as an undesired effect, Ape1 overexpression has been linked to resistance to radio- and chemotherapeutic treatments in several human tumors. Inhibition of Ape1 using siRNA or the expression of a dominant negative form of the protein has been shown to sensitize cells to DNA-damaging agents, including various chemotherapeutic agents. Therefore, inhibition of the enzymatic activity of Ape1 might result in a potent antitumor therapy. A number of small molecules have been described as Ape1 inhibitors; however, those compounds are in the early stages of development. Herein we report the identification of new compounds as potential Ape1 inhibitors through a docking-based virtual screening technique. Some of the compounds identified have invitro activities in the low-to-medium micromolar range. Interaction of these compounds with the Ape1 protein was observed by mass spectrometry. These molecules also potentiate the cytotoxicity of the chemotherapeutic agent methyl methanesulfonate in fibrosarcoma cells. This study demonstrates the power of docking and virtual screening techniques as initial steps in the design of new drugs, and opens the door to the development of a new generation of Ape1 inhibitors.Fondo de Investigaciones Sanitarias (grant PI06/1250); Ministerio Ciencia e Innovación (grant CTQ-2010-20541-C03-03); Comunidad de Madrid (SBIO-0214-2006 BIPEDD and S2010 BMD-2457 BIPEDD2); Generalitat de Catalunya; Instituto de Salud Carlos III; AMAROUTOPeer Reviewe

Combination Drive Predictions by the Muskat and Differential Tracy Material Balances Using Various Empirical Relations and Theoretical Saturation Equations

ABSTRACT Combination drive predictions by material balances require a water invasionlaw, some assumption regarding pressure decline or production rates, and asaturation equation for that part of the original reservoir which governsgas-oil ratios (unless the latter are assumed at fixed values), in addition tothe material balance. One form of the latter is the Muskat equation, which contains pressure derivatives of the volumetric fluid properties and water encroachment, the two main variables being pressure and average saturation overthe original oil zone. Another is the Tracy equation, which containspressure-dependent groups. A differential form of this equation is presented which contains pressure derivatives of the groups, and production and waterinvasion rates, with pressure and time the two main variables. Saturation equations are discussed with regard to the assumptions, particularly that ofrelease of gas in the invaded zone, this being in accordance with the material balance. The use of simple empirical equations for the various quantities issuggested. These must be of a form which give usable values for the pressureand time derivatives where required. Calculated water invasions are comparedfor various theoretical and empirical invasion formulae, with linear andexponential pressure declines. Predictions of a depletion drive by the Muskatand differential Tracy equations are compared, using various empirical relations for the required quantities. Combination performance curves are calculated by the Muskat equation for various ratios of aquifer constant topressure decline constant, both laws assumed exponential. Similar curves are calculated by the differential Tracy equation, with hyperbolic forms for waterinvasion and production rates, taking various sets of values for the constants in these forms. The calculations are programmed for a three-point Runge-Kuttamethod, taking production increments rather than pressure d4eerements where pressure stabilization or in- crease might occur. The use of such methods to optimize a production schedule is suggested. </jats:sec

Micropropagación de plantas de lechosa en recipientes de inmersión temporal a partir de brotes axilares Micropropagation of papaya plants in temporary immersion recipients from axilary shoots

Se estandarizaron las condiciones de iniciación, multiplicación, enraizamiento y aclimatización de plantas hermafroditas de lechosa cv Maradol provenientes de brotes axilares, producidos en recipientes de inmersión temporal RITA®. En cada envase, contentivo de 200 ml de medio de cultivo líquido de Fitch, se colocaron cuatro brotes de 2 a 3 cm de longitud. Los biorreactores se conectaron a tres líneas de inmersión de 5, 2 y 1 min cada 4h y se colocaron 6 envases en promedio por línea, en condiciones de fotoperíodo de 16 h. Transcurridos 30 a 45 días, se cuantificaron los brotes y se clasificaron de acuerdo al tamaño: < 2 cm (pequeños), entre 2 a 3 cm (medianos),  ˃ 3 cm con y sin raíz (grandes). Los dos primeros tipos de brotes se continuaron multiplicando en los mismos medios; y los más elongados se aclimatizaron utilizando el Sistema Autotrófico Hidropónico (SAH). Se determinó la sanidad y la fidelidad de las plantas producidas mediante pruebas de ELISA y RAPD, respectivamente. Durante un periodo de 6 meses se reciclaron un total de 47 recipientes, los cuales produjeron 1.091 brotes: 377  pequeños; 482 medianos; 175 grandes sin raíz y 57 con raíz. Usando el SAH se obtuvo 89,5% de plantas aclimatizadas cuando se usaron brotes enraizados, y 41,6% a partir de brotes sin  raíces. Con la combinación de las técnicas RITA y SAH se logró un sistema continuo y eficiente de producción de plantas sanas y fieles al tipo, en comparación con los métodos convencionales de micropropagación y aclimatización