logo

Sistema de automatización de Bibliotecas y Centro de
Documentación Universidad Mayor de San Simón

Base de datos:
articulos
Buscar:
$ []
Referencias encontradas:
Mostrando:
1 .. 20   en el formato [Largo]
página 1 de 4
ir para página            
  1 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 75    (1 / 75)

 

Título del Articulo: PROCESO DE EXTRACCIÓN DE ALMIDÓN DE YUCA POR VÍA SECA

Autor: MARIA RAQUEL ANTEZANA GOMEZ

Editorial: Scielo Bolivia

Fecha y lugar de edición: VOLUMEN 24,Cochabamba-Bolivia

Abstract:

El presente trabajo de investigación tiene como objetivo estudiar un proceso innovativo de extracción de almidón de yuca por vía seca, comouna alternativa de solución al problema decontaminación del medio ambiente que se generacuando la extracción es realizada de la maneratradicional (vía húmeda).El trabajo deinvestigación plantea un proceso en el cual seevalúan dos técnicas de extracción de una harina deyuca con características similares a las del almidóndulce. El contenido de fibra es la característicaprincipal de calidad evaluada en el producto final.Para el desarrollo del trabajo de investigación, serecurre a experiencias anteriores en la elaboraciónde harina de yuca con algunas modificaciones en elproceso, como la adición de una etapa de premolienda en húmedo

Sitio web (URL): http://www.scielo.org.bo/pdf/rbq/v24n1/v24n1a14.pdf



  2 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 74    (2 / 75)

 

Título del Articulo: Utilidad de la prueba de Montenegro (IDRM) como herramienta para la vigilancia epidemiológica de Leishmaniasis cutánea en áreas de Bolivia donde coexiste la infección por Leishmania spp y T. cruzi

Autor: ERNESTO ROJAS CABRERA

Editorial: Scielo Bolivia

Fecha y lugar de edición: 2012,Cochabamba-Bolivia

Abstract:

Objetivos: evaluar la respuesta a la prueba de la Intradermorreacción de Montenegro (IDRM) en áreas endémicas para leishmaniasis y enfermedad de Chagas.Métodos: se aplicó la IDRM a jóvenes sin antecedentes previos de leishmaniasis, en dos regiones endémicas para leishmaniasis y enfermedad de Chagas respectivamente. La prueba se aplicó en tres oportunidades con intervalo de dos meses entre aplicaciones, se evaluó la respuesta a la misma, por medición de la induración post inoculación.Resultados: No se encontró reacciones positivas de IDRM en ninguna de las dos regiones. La presencia de anticuerpos anti T. cruzi entre algunos de los participantes tampoco produjo reacciones positivas de la prueba. La inoculación de la IDRM no generó reacciones positivas al final de las tres aplicaciones. Conclusiones: por nuestros hallazgos nosotros concluimos que la IDRM podría ser utilizada como herramienta epidemiológica para leishmaniasis en Bolivia en situaciones en las que coexisten la leishmaniasis y el Chagas.

Sitio web (URL): http://www.scielo.org.bo/scielo.php?pid=S1012-29662012000200002&script=sci_arttext&tlng=es



  3 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 73    (3 / 75)

 

Título del Articulo: Leishmaniasis mucosa laríngea sin puerta de entrada evidente: presentación de un caso clínico

Autor: ERNESTO ROJAS CABRERA

Editorial: Scielo Bolivia

Fecha y lugar de edición: 2011,Cochabamba-Bolivia

Abstract:

En Bolivia se ha podido evidenciar la circulación de 5 especies de parásitos de Leishmania: L (V.) braziliensis; L (V.) lainsoni; L (V.) guyanensis;L (L) amazonensis y Leishmania (L) chagasi. El compromiso mucoso es producida principalmente por agentes que pertenecen al complejo Leishmania (Viannia) braziliensis, que habitualmente está asociado a lesiones cutáneas y mucocutáneas. Se comenta el presente caso de un paciente del sexo masculino de 34 años de edad, que por razones de trabajo permaneció durante algunos años en zona endémica para leishmania, abandonando luego sin previo antecedente de lesiones cutáneas. El reporte de la endoscopia y el informe histopatológico no definieron el diagnóstico etiológico del cuadro, pero aportaron al indicar la presencia de alteraciones granulomatosas en laringe y descartar proseso maligno o tuberculoso. Los antecedentes epidemiológicos y una prueba de Intradermorreacción de Montenegro (IDRM) positivo apoyaron la decisión de iniciar un ciclo de tratamiento con N-metil-glucamina, demostrando una muy buena evolución clínica tras ser examinado en los siguientes 6 meses después del tratamiento.

Sitio web (URL): http://www.scielo.org.bo/scielo.php?pid=S1012-29662011000200008&script=sci_arttext&tlng=en



  4 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 72    (4 / 75)

 

Título del Articulo: Leishmaniasis mucosa laríngea sin puerta de entrada evidente: presentación de un caso clínico

Autor: ERNESTO ROJAS CABRERA

Editorial: Scielo Bolivia

Fecha y lugar de edición: 2011,Cochabamba-Bolivia

Abstract:

It has been made evident in Bolivia the circulation of 5 species of Leishmania parasites. L (V)braziliensis, L(V) lainsoniL (V)guyanensis, L (L) amazonensis and Leishmania (L) chagasi. The mucosal involvement is produced mainly by parasites of the Leishmania (Viannia) braziliensis complex, which is usually associated with cutaneousand mucocutaneous lesions. It isdiscussed the case of a malepatient 34 years of age, that worked for someyears in an endemic leishmaniasis area, and heleft the endemic area without history of skin lesions. The report of endoscopy and histopathology did not define the etiologic diagnosis of leishmaniasis, but they provided evidence of granu-lomatous changes in the larynx, ruled out malignancy or tuberculosis. The epidemiological history and the positive intradermal test of Montenegro (IDRM) supported the decision to start a course of treatment with N-methyl-glucamine and demonstrated an excellent clinical improvement in the following 6 months post treatment.

Sitio web (URL): http://www.scielo.org.bo/scielo.php?pid=S1012-29662011000200008&script=sci_arttext&tlng=en



  5 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 71    (5 / 75)

 

Título del Articulo: Intralesional Antimony for Single Lesions of Bolivian Cutaneous Leishmaniasis

Autor: ERNESTO ROJAS CABRERA

Editorial: Oxford University Press

Fecha y lugar de edición: 2013,-Bolivia

Abstract:

Background. Cutaneous leishmaniasis is an ultimately self-curing disease for which systemic therapy with pentavalent antimony (Sb) is effective but with side effects. We evaluated 2 local treatments, intralesional (IL) Sb and cryotherapy, for single lesions due to Bolivian Leishmania (v.) braziliensis in a placebo-controlled study.Methods. Patients were randomized between IL Sb (650 µg/mm2 of lesion area on days 1, 3, and 5), cryotherapy (days 1 and 14), and placebo cream (daily for 20 days) in a 3:2:3 allocation. Lesion area was measured prior to therapy, and at 1, 3, and 6 months after therapy. The criteria for lesion cure were as follows: not doubling in size at 1 month, at least 50% diminution in size at 3 months, and complete reepithelialization at 6 months. Local adverse effects were recorded.Results. Cure rates were 21 of 30 (70%; 95% confidence interval [CI], 52%–83%) for IL Sb, 4 of 20 (20%; 95% CI, 8%–42%) for cryotherapy, and 5 of 30 (17%; 95% CI, 7%–34%) for placebo cream (P < .001 for IL Sb vs each other group). IL Sb adverse events were limited to injection site pain, with a mean value of 1.0 (mild).Conclusions. The comparative cure rate, small amount of drug administered, and tolerance data for IL Sb suggest that if local therapy for single L. braziliensis lesions is chosen, this treatment is attractive. Given the difficulties of performing placebo-controlled trials in the New World, the combined placebo and cryotherapy cure rate (18%; 95% CI, 10%–31%) is likely to become the standard against which future interventions for L. braziliensis are compared.Clinical Trials Registration. NCT01300975.

Sitio web (URL): https://academic.oup.com/cid/article/56/9/1255/294729



  6 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 70    (6 / 75)

 

Título del Articulo: Molecular cloning and characterization of the enzyme UDP-glucose: protein transglucosylase from potato

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: ElSevier

Fecha y lugar de edición: 1999,-

Abstract:

UDP-Glc:protein transglucosylase (UPTG) (EC 2.4.1.112) is an autocatalytic glycosyl-transferase previously postulated as a protein that primes starch biosynthesis. Polyclonal antibodies raised against UPTG purified from potato (Solanum tuberosum L.) tubers were used to screen a potato swelling stolon tip cDNA expression library. The isolation, cloning and sequencing of two cDNAs corresponding to UPTG are described. Recombinant UPTG was labelled after incubation with UDP-[14C]-Glc and Mn2+, indicating that it was enzymatically active. It was determined that purified as well as recombinant UPTG can be reversibly glycosylated by UDP-Glc, UDP-Xyl or UDP-Gal. RNA hybridization studies and western blot analysis indicate that UPTG mRNA and protein are expressed in all potato tissues. Databank searches revealed a high degree of identity between UPTG and several plant sequences that encode for proteins with apparent localization at the cytoplasmic face of the Golgi apparatus and at plasmodesmata. The biochemical properties of UPTG and the apparent lack of a signal peptide that could allow its entrance into plastids argue against the postulated role of UPTG in starch synthesis and point towards a possible role of the protein in the synthesis of cell wall polysaccharides.

Sitio web (URL): https://www.sciencedirect.com/science/article/abs/pii/S0981942899001175



  7 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 69    (7 / 75)

 

Título del Articulo: Molecular Cloning and Characterization of a Soluble Inorganic Pyrophosphatase in Potato

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: ASPB

Abstract:

A cDNA clone encoding a soluble inorganic pyrophosphatase (EC 3.6.1.1) of potato (Solanum tuberosum L.) was isolated by screening a developing tuber library with a heterologous probe. The central domain of the encoded polypeptide is nearly identical at the sequence level with its Arabidopsis homolog (J.J. Kieber and E.R. Signer [1991] Plant Mol Biol 16: 345–348). Computer-assisted analysis of the potato, Arabidopsis, and Escherichia coli soluble pyrophosphatases indicated a remarkably conserved organization of the hydrophobic protein domains. The enzymatic function of the potato protein could be deduced from the presence of amino acid residues highly conserved in soluble pyrophosphatases and was confirmed by its capacity to complement a thermosensitive pyrophosphatase mutation in E. coli. The potato polypeptide was purified from complemented bacterial cells and its pyrophosphatase activity was shown to be strictly dependent on Mg2+ and strongly inhibited by Ca2+. The subcellular location of the potato pyrophosphatase is unknown. Structure analysis of the N-terminal protein domain failed to recognize typical transit peptides and the calculated molecular mass of the polypeptide (24 kD) is significantly inferior to the values reported for the plastidic (alkaline) or mitochondrial pyrophosphatases in plants (28–42 kD). Two unlinked loci could be mapped by restriction fragment length polymorphism analysis in the potato genome using the full-length cDNA as probe.

Sitio web (URL): http://www.plantphysiol.org/content/109/3/853.short



  8 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 68    (8 / 75)

 

Título del Articulo: Molecular and cytological characterization of ribosomal RNA genes in Chenopodium quinoa and Chenopodium berlandieri

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: NRC Research Press

Fecha y lugar de edición: 2011,-

Abstract:

The nucleolus organizer region (NOR) and 5S ribosomal RNA (rRNA) genes are valuable as chromosome landmarks and in evolutionary studies. The NOR intergenic spacers (IGS) and 5S rRNA nontranscribed spacers (NTS) were PCR-amplified and sequenced from 5 cultivars of the Andean grain crop quinoa (Chenopodium quinoa Willd., 2n = 4x = 36) and a related wild ancestor (C. berlandieri Moq. subsp. zschackei (Murr) A. Zobel, 2n = 4x = 36). Length heterogeneity observed in the IGS resulted from copy number difference in subrepeat elements, small re arrangements, and species-specific indels, though the general sequence composition of the 2 species was highly similar. Fifteen of the 41 sequence polymorphisms identified among the C. quinoa lines were synapomorphic and clearly differentiated the highland and lowland ecotypes. Analysis of the NTS sequences revealed 2 basic NTS sequence classes that likely originated from the 2 allopolyploid subgenomes of C. quinoa. Fluorescence in situ hybridization (FISH) analysis showed that C. quinoa possesses an interstitial and a terminal pair of 5S rRNA loci and only 1 pair of NOR, suggesting a reduction in the number of rRNA loci during the evolution of this species. C. berlandieri exhibited variation in both NOR and 5S rRNA loci without changes in ploidy.Key words: rDNA, NOR, IGS, 5S NTS, FISH, Chenopodium.

Sitio web (URL): http://www.nrcresearchpress.com/doi/abs/10.1139/g06-033#.XBOlc2hKiUl



  9 / 75
articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 67    (9 / 75)

 

Título del Articulo: Lipoxygenase Pathway and Membrane Permeability and Composition during Storage of Potato Tubers (Solanum tuberosum L. cv Bintje and Désirée) in Different Conditions

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Wiley Online Library

Fecha y lugar de edición: 2002,-

Abstract:

Abstract: Potato tubers (Solanum tuberosum L. cv Bintje and Désirée) were stored for 12 months under three different storage conditions: 4 °C, 20 °C with sprout inhibitor and 20 °C without sprout inhibitor. Independent of the storage conditions, our results show that the increase of membrane permeability, as revealed by electrolyte leakage, is not correlated with the lipid saturation status. Moreover, there is no simple correlation between cold sweetening and membrane permeability or lipid saturation status. During storage at 20 °C without sprout inhibitor, the increase in membrane permeability is inversely correlated to sucrose accumulation, but this is not the case when tubers were stored with sprout inhibitors. Lipoxygenase (LOX) is often proposed as responsible for peroxidative damage to membrane lipids. The gradual peroxidation resulting in double bond index decrease is regarded as a cause of senescence sweetening. Our results revealed that the role of LOX in aging and senescence of potato tubers is far from clear. LOX activity and gene expression are not correlated with the fatty acids composition of the membrane. Moreover, LOX activity and fatty acid hydroperoxide content are low in older tubers, whatever the storage conditions or the varieties. On the basis of our results, the correlation between sugar accumulation (low temperature and senescence sweetening) and peroxidative damage occurring during storage of potato tubers is discussed.

Sitio web (URL): https://onlinelibrary.wiley.com/doi/full/10.1055/s-2002-20439



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 66    (10 / 75)

 

Título del Articulo: Identification of cytosolic Mg2+-dependent soluble inorganic pyrophosphatases in potato and phylogenetic analysis.

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: PubMed

Fecha y lugar de edición: 1999,-

Abstract:

Using polyclonal antibodies raised against a previously cloned potato Mg2+-dependent soluble inorganic pyrophosphatase (ppa1 gene) [8], a second gene, called ppa2, could be isolated. A single locus homologous to ppa2 was mapped on potato chromosomes, unlinked to the two loci identified for ppa1. From a phylogenetic and structural point of view, the PPA1 and PPA2 polypeptides are more closely related to prokaryotic than to eukaryotic Mg2+-dependent soluble inorganic pyrophosphatases (soluble PPases). Subcellular localization by immunogold electron microscopy, using sections from leaf parenchyma cells, showed that PPA and PPA2 are localized to the cytosol. Based on these observations, the likely phylogenetic origin and the physiological significance of the cytosolic soluble pyrophosphatases are discussed.

Sitio web (URL): https://www.ncbi.nlm.nih.gov/pubmed/10092174



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 65    (11 / 75)

 

Título del Articulo: Expression and activity of antioxidant enzymes during potato tuber dormancy

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Springer Link

Fecha y lugar de edición: 2007,-

Abstract:

The expression of antioxidant genes has been analyzed in a potato plant and during tuber dormancy. Manganese superoxide dismutase (MnSOD), cytosolic copper and zinc superoide dismutase (Cu/ZnSOD), catalase class II, cytosolic ascorbate peroxidase (APX) and glutathione peroxidase (GPX) are expressed at the RNA level in all the contexts analyzed. By contrast, the expression of the iron superoxide dismutase (FeSOD) and plastidic Cu/ZnSOD seems to be limited to green tissues, as shown by northern blots and native gels. A complex DAB-peroxidase isozyme pattern (using diaminobenzidine as substrate) has been observed in different developmental contexts analyzed, but hardly observed in tubers. During tuber dormancy, MnSOD and cytosolic Cu/ZnSOD activity was relatively constant in both Désirée and Bintje varieties while catalase activity decreases. Moreover, tuber dormancy breakage did not involve significant changes in the activity of these enzymes. On the basis of these results, the possible link between active oxygen species (AOS) metabolism and dormancy is discussed.

Sitio web (URL): https://link.springer.com/article/10.1007%2FBF02360542?LI=true



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 64    (12 / 75)

 

Título del Articulo: Evidence of intra-varietal genetic variability in the vegetatively propagated crop oca (Oxalis tuberosa Mol.) in the Andean traditional farming system

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Springer Link

Fecha y lugar de edición: 2007,-

Abstract:

Oxalis tuberosa is a vegetatively propagated tuber crop in the Andes. The peasants cultivate a great number of varieties for which genetic homogeneity has never been demonstrated. Morphological descriptors and ISSR markers were used to determine the intra-varietal diversity and the influence of the mode of conservation ex-situ vs in-situ. Molecular markers revealed an intra-varietal genetic diversity attesting that oca varieties are not pure clones. The morphological analysis was congruent with the peasant classification, contrary to the molecular markers. The comparison between both conservation strategies revealed a larger intra-varietal diversity in in-situ conditions and a genetic divergence between plants. The traditional practices are likely to be responsible of the intra-varietal polymorphism since the oca is propagated almost exclusively vegetatively. At the conservation level, differences could be explained by the sampling methods. A more integrated approach between genebanks and in-situ conservation is recommended to maintain the genetic resources of the species.

Sitio web (URL): https://link.springer.com/article/10.1007%2Fs00606-007-0605-3?LI=true



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 63    (13 / 75)

 

Título del Articulo: Development and use of microsatellite markers for genetic diversity analysis of cañahua (Chenopodium pallidicaule Aellen)

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Springer Link

Fecha y lugar de edición: 2011,-

Abstract:

Cañahua (Chenopodium pallidicaule Aellen) is a poorly studied, annual subsistence crop of the high Andes of South America. Its nutritional value (high in protein and mineral content) and ability to thrive in harsh climates make it an important regional food crop throughout the Andean region. The objectives of this study were to develop genetic markers and to quantify genetic diversity within cañahua. A set of 43 wild and cultivated cañahua genotypes and two related species (Chenopodium quinoa Willd. and Chenopodium petiolare Kunth) were evaluated for polymorphism using 192 microsatellite markers derived from random genomic cañahua sequences produced by 454 pyrosequencing of cañahua genomic DNA. Another 424 microsatellite markers from C. quinoa were also evaluated for cross-species amplification and polymorphism in cañahua. A total of 34 polymorphic microsatellite marker loci were identified which detected a total of 154 alleles with an average of 4.5 alleles per marker locus and an average heterozygosity value of 0.49. A cluster analysis, based on Nei genetic distance, clearly separated from wild cañahua genotypes from the cultivated genotypes. Within the cultivated genotypes, subclades were partitioned by AMOVA analysis into six model-based clusters, including a subclade consisting sole of erect morphotypes. The isolation by distance test displayed no significant correlation between geographic collection origin and genotypic data, suggesting that cañahua populations have moved extensively, presumably via ancient food exchange strategies among native peoples of the Andean region. The molecular markers reported here are a significant resource for ongoing efforts to characterize the extensive Bolivian and Peruvian cañahua germplasm banks, including the development of core germplasm collections needed to support emerging breeding programs.

Sitio web (URL): https://link.springer.com/article/10.1007/s10722-010-9615-z



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 62    (14 / 75)

 

Título del Articulo: Development and use of an expressed sequenced tag library in quinoa (Chenopodium quinoa Willd.) for the discovery of single nucleotide polymorphisms

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: ElSevier

Fecha y lugar de edición: 2005,-

Abstract:

Quinoa (Chenopodium quinoa Willd.) is a widely consumed food crop and a primary protein source for many of the indigenous inhabitants of the Andean region of South America. In this study, we report the development of immature seed and floral expressed sequenced tag (EST) libraries and the identification of single nucleotide polymorphisms (SNPs) for quinoa. A total of 424 cDNA clones derived from immature seed and floral tissue were sequenced and analyzed for homology with known gene sequences. Three hundred and eleven of the clones were identified as homologues of known plant proteins, 38 were homologous to Arabidopsis proteins with no known function and 75 do not share significant homology with any protein in the queried databases. Interestingly, several of the annotated ESTs were present in relatively high abundance and have putative functions related to plant defense. Based on EST sequence information, fragments of 34 ESTs were amplified and sequenced in five quinoa accessions and one related weed species, C. berlandieri. Analysis of the quinoa EST sequences revealed a total of 51 SNPs in 20 EST sequences, including 38 single-base changes and 13 insertions–deletions (indels), with an average 1 SNP per 462 base pairs (bp) and 1 indel per 1812 bp. When the C. berlandieri accession was included in the analysis, 29 of the EST clones screened had at least one SNP present and an additional 81 SNPs were identified, bringing the total number of SNPs discovered to 132 (1 per 179 bp). The EST clones and SNP markers identified in this manuscript are of particular value in ongoing efforts to characterize gene expression and regulation associated with seed development, while the SNPs identified have immediate application for genetic mapping experiments, germplasm development, and the investigation of evolutionary relationships within the genus Chenopodium.

Sitio web (URL): https://www.sciencedirect.com/science/article/pii/S0168945204004078



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 61    (15 / 75)

 

Título del Articulo: Changes in oxylipin synthesis after Phytophthora infestans infection of potato leaves do not correlate with resistance

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Elsevier

Fecha y lugar de edición: 2008,-

Abstract:

Oxylipins constitute a class of molecules notably involved in host–pathogen interactions. In the potato-Phytophthora infestans (Mont.) De Barry (P. infestans) relationships, the role of colneleic and colnelenic acids, two oxylipins resulting from the consecutive action of lipoxygenase (EC 1.13.11.12) and divinyl ether synthase (EC 1.-) on respectively linoleic and linolenic acids have been previously reported. In the present paper, five potato cultivars with contrasting resistance to P. infestans were submitted to infection. Lipoxygenase pathway response was studied at both transcriptional and metabolic levels. A Northern blot preliminary study revealed that lipoxygenase (lox1 and lox3) and divinyl ether synthase genes were clearly up-regulated 96 h after leaf inoculation with P. infestans. Profiling of free and esterified oxylipins performed 24 h, 48 h, 72 h and 96 h after inoculation, showed that esterified oxylipins are mainly produced with 9-derivatives in higher concentrations (esterified forms of colnelenic acid, 9-hydroxy octadecatrienoic acid, 9-hydroperoxy octadecatrienoic acid). Oxylipin accumulation is undetectable 24 h after infection, slightly detectable after 48 h, reaching highest concentrations after 96 h. Cultivars show slightly different oxylipin profiles but the concentration of individual oxylipins differs markedly 96 h after infection. No correlation was found between P. infestans resistance levels and oxylipin synthesis rates or concentration. To assess local and systemic effects of colneleic acid application before P. infestans infection, Bintje cultivar was sprayed with colneleic acid 72 h before inoculation. Both application modes (local and systemic) resulted in lipoxygenase pathway activation without affecting the resistance level to the pathogen.

Sitio web (URL): https://www.sciencedirect.com/science/article/abs/pii/S0981942808000648



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 60    (16 / 75)

 

Título del Articulo: preliminary study of the genetic diversity of Bolivian oca (Oxalis tuberosa Mol.) varieties maintained in situ and ex situ through the utilization of ISSR molecular markers [2007]

Autor: JORGE ANTONIO ROJAS BELTRAN

Editorial: Information Systems Division, National Agricultural Library

Fecha y lugar de edición: 2007,-

Abstract:

ISSR molecular markers have been used to investigate genetic diversity of oca (Oxalis tuberosa Mol.), an Andean neglected tuber crop species. Sampling procedure allowed a preliminary study of the genetic diversity at the intra- and intervarietal levels. Twenty tuber lots conserved in situ in the microcentre of Candelaria and ex situ in the Toralapa Centre (Bolivia) were identified. Four ISSR primers amplified a total of 25 fragments of which 17 (68%) were polymorphic. These experiments show that the structure of oca varieties is mainly based upon vernacular names with a greater differentiation among tuber lots than within them, supporting agromorphological data. ISSR technique enlightened the existence of heterogeneous varieties in oca and divergence between in situ and ex situ conservation strategies. These observations are potentially linked to the different ways of management of tubers in these two conservation systems.

Sitio web (URL): http://agris.fao.org/agris-search/search.do?recordID=US201300788644



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 59    (17 / 75)

 

Título del Articulo: SIMULTANEOUS DETERMINATION OF GLUCOSE, MALTOSE AND SUCROSE IN STARCH OF SIX VARIETIES OF CASSAVA

Autor: CINTHIA CAROLA ROJAS ARNEZ

Editorial: Scielo Bolivia

Fecha y lugar de edición: 2006,Cochabamba-Bolivia

Abstract:

An enzymatic method has been developed to simultaneously determine glucose, maltose and sucrose in tubers The principle of the method is based on an enzymatic cleavage of these disaccharides and specific measurement the resulting glucose using an enzymatic procedure described by Holm (3).The study comprises two parts; the first one includes modifications of the pretreatment method to minimize errors due to ethanol used to precipitate polymeric material interfering with the activity of α-glucosidase and invertase. In the second part the usability of the method has been probed by employing it on six samples of cassava that come from Chapare-Bolivia.

Sitio web (URL): http://www.scielo.org.bo/scielo.php?pid=S0250-54602006000100004&script=sci_arttext



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 58    (18 / 75)

 

Título del Articulo: PROXIMAL COMPOSITION AND MINERAL CONTENTS OF SIX VARIETIES OF CASSAVA (MANNIHOT ESCULENTA, CRANTZ), FROM BOLIVIA

Autor: CINTHIA CAROLA ROJAS ARNEZ

Editorial: Scielo Bolivia

Fecha y lugar de edición: 2006,Cochabamba-Bolivia

Abstract:

In recent years, the Bolivia’s government has triedto develop in the tropical region of Cochabamba,Chapare. This region is tropical and is considered avery rich in natural resources; fruits, vegetablesand roots. One of the main crops in this area issweet cassava (Mannihot esculenta Crantz)The cassava’s production has a vital importancefrom a social and economic perspective accordingto regional plans of development. It has animportance to the local farmers both as a crop forconsumption within the household as well as acrop for trade

Sitio web (URL): http://www.scielo.org.bo/pdf/rbq/v24n1/v24n1a13.pdf



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 57    (19 / 75)

 

Título del Articulo: Macromolecular Geometries Determined with Field-Flow Fractionation and their Impact on the Overlap Concentration

Autor: CINTHIA CAROLA ROJAS ARNEZ

Editorial: ACS Publication

Fecha y lugar de edición: 2008,Cochabamba-Bolivia

Abstract:

In this paper we aim to understand the size/conformation relationship in waxy barley starch, a polydisperse and ultrahigh molar mass biomacromolecule. Characterizations are performed with asymmetrical flow field-flow fractionation (AsFlFFF). Furthermore, we study the effect of homogenization on the molar mass, rms radius (rrms) and hydrodynamic radius (rh). For the untreated sample, the macromolecules are elongated objects with low apparent density. As a result of homogenization, molar mass, and rrms decrease, while rh remains unaffected. The process also induces an increase, and scaling with size, of apparent density as well as changes in conformation, represented qualitatively by rrms/rh. Finally, results from AsFlFFF are compared with viscosimetry and discussed in terms of concentration and close-packing in relation to macromolecular shape and conformation. Hence, the results show that AsFlFFF and our novel methodology enable the determination of several physical properties with high relevance for the solution behavior of polydisperse macromolecules.

Sitio web (URL): https://pubs.acs.org/doi/abs/10.1021/bm800127n



articulos
seleccionar
imprimir

Como citar este artículo
Exportar a BibTex
Exportar a Reference Manager
Exportar a Pro Cite
Exportar a End Note
Exportar a Refworks
Registro: 56    (20 / 75)

 

Título del Articulo: PLANTELES DE CUYES LOCALES E INTRODUCIDOS EN BOLIVIA

Autor: ELIZABETH RICO NUMBELA

Editorial: PLANTELES DE CUYES LOCALES E INTRODUCIDOS EN BOLIVIA

Fecha y lugar de edición: 2010,-Bolivia

Abstract:

Las poblaciones que tienen rasgos genéticos particulares y únicos se denominan recursosgenéticos (Hodges, 1990 y Hammond, 1994). Latinoamérica posee una amplia diversidad derecursos genéticos animales, los cuales son empleados en diferentes sistemas y bajo variadascondiciones ecológicas y sociales (Hammond, 1994 y Cundiff, 2000). El cuy es un recurso genéticoque posee características que son únicas en ambientes específicos. Por consiguiente, es unmaterial genético valioso que necesita ser protegido, mantenido y mejorado como la base parapolíticas y programas nacionales de mejoramiento.FAO (1997), menciona que los problemas a que se enfrentan los recursos genéticos animales en elmundo son los siguientes: La disminución de la variabilidad genética dentro de razas o líneas dealta producción, empleadas en sistemas intensivos de producción; la rápida desaparición de razaslocales a través de la introducción de razas exóticas y los climas cálidos, húmedos y otrosambientes hostiles comunes a los países en desarrollo. Por tanto, es necesario desarrollarprogramas de acción sobre el manejo sostenible, preservación (in situ y ex situ) y banco de datosde recursos genéticos locales de acuerdo con los sistemas de producción sostenibles.

Sitio web (URL): http://www.dicyt.umss.edu.bo/archivos/Rico_Numbela.pdf





página 1 de 4
ir para página            

Base de datos  articulos : Formulario avanzado

   
Buscar:
en el campo:
 
1     
2   
3   
 
Siguenos en     
Contacto: +591 04 4221486
bibliotecas@dicyt.umss.edu.bo
Derechos Reservados 2019 - Universidad Mayor de San Simon - DICyT