Rescate de embriones para la obtención de vitroplantas de vid (vitis vinífera l.)

Título en ingles: Embryos rescue for the obtaining of grapevine (Vitis vinifera L.) vitroplantsResumen: Este trabajo es la primera fase de un macroproyecto sobre la optimización de un protocolo para la obtención de metabolitos secundarios de interés comercial mediante la utilización de suspensiones celulares de Vid (Vitis vinífera L.). Se investigó el rescate de embriones como alternativa para la obtención de vitroplantas de vid (Vitis vinífera L.). El material vegetal utilizado se obtuvo de frutos de vid variedad Red Globe comerciales. Las semillas se desinfectaron sumergiéndolas en 5 g/l de ácido dicloroisocianúrico (NaDCC) por 15 min y luego en 2 g/l de Benomyl® por 15 min, con una efectividad del 92%. Se realizaron diferentes tratamientos para la obtención de plántulas utilizando semillas como explantes, las cuales se cultivaron en el medio Murashige Skoog suplementado con diferentes concentraciones de ácido indolacético (AIA) en combinación con ácido giberélico (AG3) y kinetina (K) sin obtener respuesta favorable para la germinación. Como alternativa, se extrajeron semillas inmaduras de frutos de la planta y se colocaron en el mismo medio  pero suplementado con 100 mg/l de polivinilpirrolidona (PVP), 0.35 mg/l de AG3 y 1.75 mg/l de AIA por un mes. Posteriormente, se abrieron las semillas y se realizó el rescate de embriones, sembrándolos bajo condiciones de oscuridad por ocho días en los medios de cultivo Murashige Skoog 1 y 2 modificados, encontrando la formación de vitroplantas en un 40% al mes de cultivo. Abstract: This work is the first phase of a macroproyect about the optimization of a protocol for the obtaining of secondary metabolites of commercial interest by means of the use of cellular suspensions of Vitis vinífera L. The embryos rescue was investigated as alternative for the obtaining of grapevine (Vitis vinífera L.) vitroplants. The vegetable material used was obtained from commercial fruits of grapevine Red Globe variety. The seeds were disinfected submerging them in 5 g/l of dicloroisocianuric acid (NaDCC) for 15 min, and then in Benomyl® 2 g/l for 15 min, with an effectiveness of 92%. Different treatments were performed to obtain plants using seeds as explants, which were cultured on Murashige Skoog medium supplemented with different concentrations of indole acetic acid (AIA) in combination with gibberellic acid (AG3) and kinetin (K) without obtaining favorable answer for the germination. As alternative, immature seeds were extracted from grape fruits and placed on Murashige Skoog medium supplemented with 100 mg/l polyvinyl pyrrolidone (PVP), 0.35 mg/l of gibberellic acid and 1.75 mg/l of indol acetic acid for a month. Seeds were then opened and performed embryo rescue, planting them under dark conditions for eight days in the culture media Murashige Skoog 1 and 2 modified, finding plants formation by 40% a month after growing

Caracterización fisicoquímica, actividad antioxidante y contenido de fenoles y flavonoides totales de nopal morado (Opuntia gosseliniana) en dos etapas de coloración

Nopal (Opuntia gosseliniana) is considered a food product of interest due to its functional properties, including its antioxidant activity. The objective of this work was to evaluate the physical-chemical properties (color, pH and total soluble solids), antioxidant activity (DPPH, ABTS and FRAP), content of total phenols and flavonoids and betalain content of ethanolic extracts of nopal in two stages of coloration: green and purple. The highest values for total phenols and flavonoids were found in the purple samples, with values of 2.31 mg EAG/gps and 3.06 mg EQ/gps, respectively. Similarly, in the antioxidant activity (in the three techniques used) and betalain content, higher values were obtained in the purple color stage. Therefore, this species of cacti could be a potential source of antioxidants and pigments of agroindustrial interest.El nopal (Opuntia gosseliniana) es considerado un producto alimenticio de interés debido a sus propiedades funcionales, incluyendo su actividad antioxidante. El objetivo de este trabajo fue evaluar las propiedades físico-químicas (color, pH y sólidos solubles totales), actividad antioxidante (DPPH, ABTS y FRAP), contenido de fenoles y flavonoides totales y contenido de betalaínas extractos etanólicos de nopal en dos etapas de coloración: verde y morado. Los valores más altos para fenoles y flavonoides totales se encontraron en las muestras de color morado, con valores de 2.31 mg EAG/gps y 3.06 mg EQ/gps, respectivamente. De igual manera, en la actividad antioxidante se obtuvieron valores más altos en la etapa de color morado en las tres técnicas utilizadas. Por lo que, esta especie de cactácea podría ser una fuente potencial de antioxidantes y pigmentos de interés agroindustrial

Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth (Eichhornia crassipes) and two algae (Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3–8.4, whereas COD reduced by 50–65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to <0.1 mg/L, Chlorodesmis sp. was able to reduce arsenic by 40−50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation

Inhibition of N1-Src kinase by a specific SH3 peptide ligand reveals a role for N1-Src in neurite elongation by L1-CAM

In the mammalian brain the ubiquitous tyrosine kinase, C-Src, undergoes splicing to insert short sequences in the SH3 domain to yield N1- and N2-Src. We and others have previously shown that the N-Srcs have altered substrate specificity and kinase activity compared to C-Src. However, the exact functions of the N-Srcs are unknown and it is likely that N-Src signalling events have been misattributed to C-Src because they cannot be distinguished by conventional Src inhibitors that target the kinase domain. By screening a peptide phage display library, we discovered a novel ligand (PDN1) that targets the unique SH3 domain of N1-Src and inhibits N1-Src in cells. In cultured neurons, PDN1 fused to a fluorescent protein inhibited neurite outgrowth, an effect that was mimicked by shRNA targeting the N1-Src microexon. PDN1 also inhibited L1-CAM-dependent neurite elongation in cerebellar granule neurons, a pathway previously shown to be disrupted in Src(−/−) mice. PDN1 therefore represents a novel tool for distinguishing the functions of N1-Src and C-Src in neurons and is a starting point for the development of a small molecule inhibitor of N1-Src

A proteomics approach to decipher the molecular nature of planarian stem cells

Background In recent years, planaria have emerged as an important model system for research into stem cells and regeneration. Attention is focused on their unique stem cells, the neoblasts, which can differentiate into any cell type present in the adult organism. Sequencing of the Schmidtea mediterranea genome and some expressed sequence tag projects have generated extensive data on the genetic profile of these cells. However, little information is available on their protein dynamics. Results We developed a proteomic strategy to identify neoblast-specific proteins. Here we describe the method and discuss the results in comparison to the genomic high-throughput analyses carried out in planaria and to proteomic studies using other stem cell systems. We also show functional data for some of the candidate genes selected in our proteomic approach. Conclusions We have developed an accurate and reliable mass-spectra-based proteomics approach to complement previous genomic studies and to further achieve a more accurate understanding and description of the molecular and cellular processes related to the neoblasts

Challenges for Allergy Diagnosis in Regions with Complex Pollen Exposures

Over the past few decades, significant scientific progress has influenced clinical allergy practice. The biological standardization of extracts was followed by the massive identification and characterization of new allergens and their progressive use as diagnostic tools including allergen micro arrays that facilitate the simultaneous testing of more than 100 allergen components. Specific diagnosis is the basis of allergy practice and is always aiming to select the best therapeutic or avoidance intervention. As a consequence, redundant or irrelevant information might be adding unnecessary cost and complexity to daily clinical practice. A rational use of the different diagnostic alternatives would allow a significant improvement in the diagnosis and treatment of allergic patients, especially for those residing in complex pollen exposure areas

Molecular characterization of occult hepatitis B virus infection in patients with end-stage liver disease in Colombia.

ABSTARCT: Hepatitis B virus (HBV) occult infection (OBI) is a risk factor to be taken into account in transfusion, hemodialysis and organ transplantation. The aim of this study was to identify and characterize at the molecular level OBI cases in patients with end-stage liver disease. METHODS: Sixty-six liver samples were obtained from patients with diagnosis of end-stage liver disease submitted to liver transplantation in Medellin (North West, Colombia). Samples obtained from patients who were negative for the surface antigen of HBV (n = 50) were tested for viral DNA detection by nested PCR for ORFs S, C, and X and confirmed by Southern-Blot. OBI cases were analyzed by sequencing the viral genome to determine the genotype and mutations; additionally, viral genome integration events were examined by the Alu-PCR technique. RESULTS: In five cases out of 50 patients (10%) the criteria for OBI was confirmed. HBV genotype F (subgenotypes F1 and F3), genotype A and genotype D were characterized in liver samples. Three integration events in chromosomes 5q14.1, 16p13 and 20q12 affecting Receptor-type tyrosine-protein phosphatase T, Ras Protein Specific Guanine Nucleotide Releasing Factor 2, and the zinc finger 263 genes were identified in two OBI cases. Sequence analysis of the viral genome of the 5 OBI cases showed several punctual missense and nonsense mutations affecting ORFs S, P, Core and X. CONCLUSIONS: This is the first characterization of OBI in patients with end-stage liver disease in Colombia. The OBI cases were identified in patients with HCV infection or cryptogenic cirrhosis. The integration events (5q14.1, 16p13 and 20q12) described in this study have not been previously reported. Further studies are required to validate the role of mutations and integration events in OBI pathogenesis

A degenerate primer MOB typing (DPMT) method to classify gamma-proteobacterial plasmids in clinical and environmental settings

Transmissible plasmids are responsible for the spread of genetic determinants, such as antibiotic resistance or virulence traits, causing a large ecological and epidemiological impact. Transmissible plasmids, either conjugative or mobilizable, have in common the presence of a relaxase gene. Relaxases were previously classified in six protein families according to their phylogeny. Degenerate primers hybridizing to coding sequences of conserved amino acid motifs were designed to amplify related relaxase genes from γ-Proteobacterial plasmids. Specificity and sensitivity of a selected set of 19 primer pairs were first tested using a collection of 33 reference relaxases, representing the diversity of γ-Proteobacterial plasmids. The validated set was then applied to the analysis of two plasmid collections obtained from clinical isolates. The relaxase screening method, which we call "Degenerate Primer MOB Typing" or DPMT, detected not only most known Inc/Rep groups, but also a plethora of plasmids not previously assigned to any Inc group or Rep-type