Search

Practical implications The case of the Peruvian Amazon Company, explores how an unsustainable business model could eventually lead a once successful company to its death. The contribution of the following chapter is based on the description of the causes of the Peruvian Amazon Company’s death. Previous studies had analysed the internationalization strategies implemented by the company. Although, an evaluation of causes of the company’s real extinction had not been presented.

En este estudio se muestra que aunque no hay evidencia de un patrón generalizable en el proceso de internacionalización de compañías colombianas, hay algunos rasgos comunes en la mayoría de las empresas observadas: la elección de exportaciones como el modo de entrada inicial, el ingreso a países con baja distancia psicológica y geográfica, y el desarrollo de ventajas estratégicas locales que eventualmente se replican en el exterior. Se utilizaron una encuesta y una entrevista estructurada que incluyen variables numéricas y categóricas seguido de un análisis cruzado de casos. También se encontró que las decisiones de internacionalización operan bajo una base ad-hoc y dependen de la experiencia y la intuición de los altos ejecutivos de las empresas

Micromonospora is a Gram-positive bacterium that can be isolated from nitrogen-fixing root nodules from healthy leguminous plants and promotes plant growth. Selected strains of Micromonospora isolated in our laboratory from alfalfa root nodules showed in vitro antifungal activity against several pathogenic fungi. Moreover, root inoculation of tomato plants with these Micromonospora strains effectively reduced leaf infection by the fungal pathogen Botrytis cinerea, despite temporal and spatial separation between the inoculation of both microorganisms. Although Micromonospora improves plant growth and has antifungal activity against plant pathogens, the interaction between Micromonospora and AM fungi has not been studied before. Thus, the aim of the study was to work on the understanding of this interaction. The results obtained allow us to conclude that Micromonospora strains ALFpr18c and ALFb5 did not adversely affect the colonization and development of the AM fungi R. irregularis and F. mosseae on plant root. Micromonospora strain ALFpr18c increased the beneficial effect of the AM fungi on shoot dry weight of alfalfa and tomato when the AM fungi were established first on the roots. Therefore, it is possible to use Micromonospora ALFpr18c combined with AM fungi to improve plant growth. Micromonospora strains should be considered excellent plant probiotic bacteria as they combine plant growth-promoting activity with both direct antifungal activity against plant pathogens and the ability to prime plant immunity and did not adversely affect the colonization and development of the AM fungi.

Arbuscular mycorrhizal (AM) is a mutually beneficial interaction among higher plants and soil fungi of the phylum Glomeromycota. Numerous studies have pointed that jasmonic acid plays an important role in the development of the intraradical fungus. This compound belongs to a group of biologically active compounds known as oxylipins which are derived from the oxidative metabolism of polyunsaturated fatty acids. Studies of the regulatory role played by oxylipins in AM colonization have generally focused on jasmonates, while few studies exist on the 9-LOX pathway of oxylipins during AM formation. Here, the cDNA of Allene oxide synthase 3 (AOS3), a key enzyme in the 9-LOX pathway, was used in the RNA interference (RNAi) system to transform potato plants in order to suppress its expression. Results show increases in AOS3 gene expression and 9-LOX products in roots of wild type potato mycorrhizal plants. The suppression of AOS3 gene expression increases the percentage of root with mycorrhizal colonization at early stages of AM formation. AOS3 RNA interference lead to an induction of LOXA and 13-LOX genes, a reduction in AOS3 derived 9-LOX oxylipin compounds and an increase in jasmonic acid content, suggesting compensation between 9 and 13-LOX pathways. The results in a whole support the hypothesis of a regulatory role for the 9-LOX oxylipin pathway during mycorrhization., We wish to thank the Tomato Genetics Resource Centre (TGRC) of the University of California for providing tomato seeds. We would also like to thank Michael O’Shea for proof-reading the document. LC-MS/MS analyses were carried out by Dr. Lourdes Sánchez-Moreno at the Scientific Instrumentation Service of the Estación Experimental del Zaidín (CSIC), Granada, Spain. This study was supported by grants from the Comisión Interministerial de Ciencia y Tecnología (CICYT) and Fondos Europeos de Desarrollo Regional (FEDER) through the Ministerio de Economía y Competitividad in Spain (AGL2011-25930; AGL2014-52298-P) as well as the Junta de Andalucía (Research Group BIO 260). R. J. León was supported by a research fellowship from the CSIC-JAE program.

Healthy food consumption has increased the production of fruit based value-added products as a result of the awareness of their high contents of bio-active compounds like vitamins, minerals, dietary fiber and antioxidants. High moisture content in fruits can generate losses in post-harvest storage. The dehydration process based on water activity reduction, is an option for overcoming such losses. Regular hot air drying could affect negatively the quality properties of the fruit due to the long times at high temperature. Power ultrasound (US) application during the convective drying has been used as a new method to decrease drying time. The aim of this work was to evaluate the effect of the convective drying assisted by ultrasound on drying time and aroma losses of tamarillo (TS) and mango slices (MS). An experimental design was developed, showing the positive effect of ultrasound during convective drying process. Power ultrasound (20 kHz, 45 W) was applied during drying test at 50°C, applying 5 and 10 minutes of ultrasound each half hour intermittently. Weight loss of samples was measured every hour until moisture content of 10.0±1.0% (wet basis). Aroma measurement was development by SPME method. The results were compared with fresh fruit data for all tests.

a b s t r a c t A total of 150 isolates of endophytic fungi were obtained from roots of Myrtus communis grown in the Mediterranean area. Seven different endophytic fungi taxa, all belonging to the Ascomycota phylum were found. Arbuscular mycorrhizal (AM) fungi, belonging to the Glomus genus, were also present in roots of M. communis. None of the root endophytic fungi tested, except Drechslera sp., colonized the root of sorghum. Among all fungi tested, only Phoma schachtii and Cylindrocarpon destructans significantly increased the shoot dry weight of sorghum grown in sterilized soil. Phomopsis columnaris, P. schachtii, Eucasphaeria sp. and Cylindrocarpon pauciseptatum increased the dry matter of sorghum grown in unsterilized soil. The percentage of AM colonization of sorghum was increased significantly only when Ph. columnaris, P. schachtii, the two strains of Bionectria ochroleuca, Eucasphaeria sp. and C. pauciseptatum were applied to unsterilized soil. The number of CFUs of endophytic fungi inoculated in sorghum rhizosphere was similar throughout the experiment, except B. ochroleuca-1 whose population increased at the end of the experiment either in sterilized or in unsterilized soil. No significant effect of the endophytic fungi isolated from M. communis on shoot and root P, K, Ca, Na, Mg, Cu and Zn concentrations of plants grown in sterilized or unsterilized soils, except Eucasphaeria sp. which increased the shoot P concentration of sorghum grown in unsterilized soil.

Gaeumannomyces graminis var. tritici causes take-all disease, the most important root disease of cereal plants. Cereal plants are able to form a symbiotic association with soil-borne arbuscular mycorrhizal fungi which can provide bioprotection against soil-borne fungal pathogens. However, the bioprotective effect of arbuscular mycorrhizal fun gi against soil-borne fungal pathogens might vary. In the present study we tested the systemic bioprotective effect of the arbuscular mycorrhizal fungi Glomus mosseae, Glomus intraradices and Gigaspora rosea against the soilborne fungal pathogen Gaeumannomyces graminis var. tritici in a barley split-root system. Glomus intraradices, Glomus mosseae and Gigaspora rosea colonized the split-root system of barley plants at different levels; however, all arbuscular mycorrhizal fungi clearly reduced the level of root lesions due to the pathogen Gaeumannomyces graminis. Our data indicate that some arbuscular mycorrhizal fungi need high root colonization rates to protect plants against fungal pathogens, whereas others act already at low root colonization rates.

The establishment of an arbuscular mycorrhizal (AM) symbiotic interaction is a successful strategy for the promotion of substantial plant growth, development, and fitness. Numerous studies have supported the hypothesis that plant hormones play an important role in the establishment of functional AM symbiosis. Particular attention has been devoted to jasmonic acid (JA) and its derivates, which are believed to play a major role in AM symbiosis. Jasmonates belong to a diverse class of lipid metabolites known as oxylipins that include other biologically active molecules. Recent transcriptional analyses revealed up-regulation of the oxylipin pathway during AM symbiosis in mycorrhizal tomato roots and indicate a key regulatory role for oxylipins during AM symbiosis in tomato, particularly those derived from the action of 9-lipoxygenases (9-LOXs). Continuing with the tomato as a model, the spatial and temporal expression pattern of genes involved in the 9-LOX pathway during the different stages of AM formation in tomato was analysed. The effects of JA signalling pathway changes on AM fungal colonization were assessed and correlated with the modifications in the transcriptional profiles of 9-LOX genes. The up-regulation of the 9-LOX oxylipin pathway in mycorrhizal wild-type roots seems to depend on a particular degree of AM fungal colonization and is restricted to the colonized part of the roots, suggesting that these genes could play a role in controlling fungal spread in roots. In addition, the results suggest that this strategy of the plant to control AM fungi development within the roots is at least partly dependent on JA pathway activation.

El deporte, como componente fundamental en la formación integral de personas, encuentra en la cultura su riqueza, como instrumento de valoración al sentido de lugar en todas las regiones del mundo. El juego de pelota prehispánico, con sus más de tres mil años de existencia, merece la categoría de juego olímpico histórico, a partir de su aporte cultural. Frente a dicho objetivo, la triangulación hermenéutica, como método, permite tener una interpretación sobre la relación entre deporte y cultura. Como resultado de esta investigación, la ciudad pirámide de Xochicalco, perteneciente al período Epiclásico mesoamericano, sirve de ejemplo para entender la motivación del deportista, que se dio en ese caso y en su modalidad sagrada, en la tensión entre el inframundo y la existencia en un mundo superior.The sport like fundamental component in the integral formation of persons finds in the culture his wealth as instrument of valuation to the sense of place in all the regions of the world. The pre-Hispanic ball game, with more than three thousand years of existence, deserves the category of Olympian historical game from his cultural contribution. With this objective the hermeneutics as a method of triangulation allows an interpretation of the relationship between sport and culture. As a result of this research, the pyramid city of Xochicalco, belonging to the Mesoamerican Epiclasic period, serves as an example to understand the motivation of the athlete, who gave itself in this case and in the sacred modality, in the tension between the underworld and the existence in a higher world.

The saprophytic fungi Aspergillus niger, Coriolopsis rigida, Fusarium lateritium, F. oxysporum, Mucor racemosus, Paecilomyces farinosus, Penicillium chrysogenum, P. restrictum, Trametes versicolor, Trichoderma harzianum, T. pseudokoningii and T. viride were able to decrease the growth in vitro of Verticillium dahlie in the presence of aqueous extract of olive residue. The conidia number of V. dahliae decreased when grown on aqueous extract of olive residue, autoclaved or filtered through 0.45 micron filters after culture of the fungi. These results suggest not only the predominance of suppressive substances of a biological nature, but also the existence of non-biological inhibitory substances. The olive residue decreased the negative effect of V. dahliae on shoot and root dry weight of tomato (Solanum lycopersicum L.), by the antifungal compounds present in the olive residue and by the antifungal substances produced by the antagonistic saprophytic fungi grown in this residue.

Systemic lupus erythematosus is a serious autoimmune disease that causes significant morbidity and mortality. It is also a disease for which several clinical differences among ethnic groups have been documented. Until recently, Hispanics, as separate patient cohort, had not been included in these studies. As a result, there is currently little information concerning its characteristics both at the clinical and at the molecular levels. With the currently available data, we can ascertain that this population exhibits considerable heterogeneity, in which some genetic mutations have been detected that may confer greater susceptibility and/or protection against the disease. The important differences in the clinical manifestations include a higher rate of renal complications as well as greater mortality. The latter may be due, at least in part, to lower socio-economic levels and inappropriate access to health care. However, given the limited data available that have focused on potential molecular mechanisms that may affect the Hispanic population affected with lupus, we cannot conclude that all the differences in disease outcome, complications, and severity that affect this patient population may be due to sociological factors. We conclude that more research is required to evaluate potential genetic and molecular factors that affect Hispanic lupus patients.

The effect of the arbuscular mycorrhizal symbiosis (AM) varies in plant cultivars. In the present study, we tested whether wild-type, old and modern tomato cultivars differ in the parameters of the AM interaction. Moreover, the bioprotective effect of AM against the soilborne tomato pathogen Fusarium oxysporum f. sp. lycopersici (Fol) was tested in the different cultivars. Ten tomato cultivars were inoculated with the arbuscular mycorrhizal fungus (AMF) Glomus mosseae alone or in combination with Fol. At the end of the experiment, AM root colonization, Fusarium infection, and the plant fresh weight was determined. The tomato cultivars differed in their susceptibility to AMF and Fol, but these differences were not cultivar age dependent. In all the cultivars affected by Fol, mycorrhization showed a bioprotective effect. Independent of the cultivar age, tomato cultivars differ in their susceptibility to AMF and Fol and the bioprotective effect of mycorrhization, indicating that the cultivar age does not affect the AM parameters tested in this study.

The systemic effect of root colonization by the arbuscular mycorrhizal fungus (AMF) Glomus mosseae on the susceptibility of old and modern barley varieties to the soil-borne fungal pathogen Gaeumannomyces graminis var. tritici (Ggt) was studied in a split-root system. Plants were precolonized on one side of the split-root system with the AMF and thereafter the other side of the split-root system was inoculated with the pathogen. At the end of the experiment the level of bioprotection was estimated by quantifying lesioned roots and the determination of the root fresh weight. AM root colonization provided protection in some of the barley genotypes tested, but not in others. This protective effect seemed to vary in the oldest and the most modern barley variety tested.

Byproducts generated from food industries, such as olive oil mills, have been studied to decrease harmful pollution and their environmental consequences. In this work, a new thermal pretreatment and saprobic fungal incubation to detoxify alperujo (two-phase olive mill waste) have been evaluated in view of its use as fertilizer in agriculture. The sequential use of both methods simplifies the thermal conditions and incubation times of the fungal treatment. Optimization of the thermal treatment from 150 to 170 °C for 45 and 15 min, respectively, reduced the incubation time with Coriolpsis rigida from 20 to 10 weeks needed to reduce phytotoxic effects on tomato plants. Therefore, the combination of thermal and biological treatments will allow the development of the potential benefits of alperujo to improve nutrients in agricultural soil., Financial support for this study was provided by the Junta de Andalucía (PO6-AGR-01906) and the Ministerio de Ciencia e Innovación (AGL2008-00572, AGL2009-12352).

Eur J Clin Invest 2011; 41 (10): 1037–1046 Abstract Background Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-degrading enzyme which suppresses T lymphocyte activity and induces Foxp3+ CD4+ regulatory T cells (Tregs) polarisation. The aim of this study was to evaluate the expression of IDO in freshly isolated peripheral cells as well as to enumerate Tregs and Th17 subpopulation in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients. Materials and methods The percentage of IDO-expressing cells as well as Tregs and Th17 was evaluated in 14 active RA- (aRA), 13 inactive RA- (iRA), 7 aSLE-, 12 iSLE-treated patients and 11 healthy donors (controls). Intracellular IDO was analysed by flow cytometry in CD14+, CD8α+, CD16+ and CD123+ cell subpopulations. Tregs and Th17 were assessed by intracellular of Foxp3 and IL17A detection in CD4+ CD14− cells. A total of 50,000 events were recorded for each sample. Results The amounts of CD14+/CD16−/IDO+, CD14−/CD16+/IDO+ and CD14+/CD16+/IDO+-expressing peripheral cells were slightly lower in inactive vs. active disease in RA and SLE patients. Notwithstanding, only inactive patients had statistically significant lower percentages when compared to controls. aRA and iRA showed a statistically significant decrease in CD8α+/CD123+/IDO+ vs. controls. Meanwhile, only iSLE patients had lower CD8α+/CD123+/IDO+ cells vs. aSLE patients and controls. Th17 subset was present in higher amounts in aRA and iRA patients vs. controls. Tregs showed an increase in aRA patients vs. controls. Conclusions A decreased percentage of IDO-expressing peripheral cells were determined in iRA and iSLE compared to controls. It could play a critical role in tolerance loss in these diseases.

We investigated the relationship between ABA and ethylene regulating the formation of the arbuscular mycorrhiza (AM) symbiosis in tomato (Solanum lycopersicum) plants and tried to define the specific roles played by each of these phytohormones in the mycorrhization process. We analysed the impact of ABA biosynthesis inhibition on mycorrhization by Glomus intraradices in transgenic tomato plants with an altered ethylene pathway. We also studied the effects on mycorrhization in sitiens plants treated with the aminoethoxyvinyl glycine hydrochloride (AVG) ethylene biosynthesis inhibitor and supplemented with ABA. In addition, the expression of plant and fungal genes involved in the mycorrhization process was studied. ABA biosynthesis inhibition qualitatively altered the parameters of mycorrhization in accordance with the plant's ethylene perception and ethylene biosynthesis abilities. Inhibition of ABA biosynthesis in wild-type plants negatively affected all the mycorrhization parameters studied, while tomato mutants impaired in ethylene synthesis only showed a reduced arbuscular abundance in mycorrhizal roots. Inhibition of ethylene synthesis in ABA-deficient sitiens plants increased the intensity of mycorrhiza development, while ABA application rescued arbuscule abundance in the root's mycorrhizal zones. The results of our study show an antagonistic interaction between ABA and ethylene, and different roles of each of the two hormones during AM formation. This suggests that a dual ethylene-dependent/ethylene-independent mechanism is involved in ABA regulation of AM formation.

We examined whether the reduced mycorrhization of abscisic acid (ABA)-deficient tomato mutants correlates with their incapacity in ABA biosynthesis and whether this effect is dependent on ethylene production. The mycorrhization of notabilis and sitiens mutants, which have different ABA deficiencies and an excess of ethylene production, was analyzed. Comparative analysis of the ABA-deficient tomato mutants showed both quantitative and qualitative differences in the pattern of arbuscular mycorrhiza (AM) colonization between the two tomato mutant phenotypes. The sitiens mutant showed a great limitation in fungal colonization (mycorrhizal intensity and arbuscule formation) well correlated with their incapacity in ABA biosynthesis. The notabilis plants, which maintained normal ABA levels in roots under our experimental conditions, appeared to be less affected in their capacity for AM formation, and only a decrease in mycorrhizal intensity was noted at the end of the mycorrhization process. Blockage of ABA formation after tungstate application resulted in a reduction in mycorrhization of wild-type tomato plants. The transcript accumulation of the mycorrhiza-responsive LePT4 gene (tomato phosphate transporter) was clearly associated with the ABA content and mycorrhiza development in roots, as the tungstate treatment in wild-type plants and the inherent ABA deficiency in sitiens mutants led to a complete abolishment of their expression. Our results suggest that the decrease in arbuscular abundance in mycorrhizal sitiens roots is directly associated with their ABA biosynthesis deficiency, and the accumulation of ethylene, as a consequence of ABA deficiency in the mutants, primarily affects mycorrhizal intensity.

Summary Pea (Pisum sativum) is an important grain legume crop whose cultivation in the Mediterranean basin and West Asia is severely constrained by infection by the weedy root parasite Orobanche crenata (crenate broomrape). Pea is a false host of other species such as O. minor, O. foetida and Phelipanche aegyptiaca. In the present experiments, we demonstrate that seed germination of the Orobanche and Phelipanche species examined is reduced in the presence of root exudates from pea plants colonised by arbuscular mycorrhizal (AM) fungi, Glomus mosseae and G. intraradices. Reduced germination was due to the effect of the AM fungi and not to the microbial populations potentially present in the soil inoculum. This protective effect of mycorrhizae was noticeable after 35 days of AM colonisation for O. crenata, O. foetida and P. aegyptiaca, but at least 45 days of colonisation were needed to get some reduction of O. minor germination.

The presence of high concentrations of arsenic (As) decreased the shoot and root dry weight, chlorophyll and P and Mg content of Eucalyptus globulus colonized with the arbuscular mycorrhizal (AM) fungi Glomus deserticola or G. claroideum, but these parameters were higher than in non-AM plants. As increased the percentage of AM length colonization and succinate dehydrogenase (SDH) activity in the root of E. globulus. Trichoderma harzianum, but not Trametes versicolor, increased the shoot and root dry weight, chlorophyll content, the percentage of AM root length colonization and SDH activity of E. globulus in presence of all As concentrations applied to soil when was inoculated together with G. claroideum. AM fungi increased shoot As and P concentration of E. globulus to higher level than the non-AM inoculated controls. The contribution of the AM and saprobe fungi to the translocation of As from root to shoot of E. globulus is discussed.

Olive oil extraction generates large amounts of olive mill residues (DOR) which may be used as fertilizer. The influence of arbuscular mycorrhizal (AM) on the phytotoxicity of dry olive residue (DOR) transformed with saprophytic fungi was studied. Aqueous extraction of DOR gave an (ADOR) fraction and an exhausted (SDOR) fraction, both of which had less phytotoxicity for tomato than the original DOR. The saprophytic fungiTrametes versicolor andPycnoporus cinnabarinus further decreased the phytotoxicity of ADOR and SDOR on tomato. The decrease of phenols concentration and the differences in the level of laccase activity caused by these fungi suggest did not account fully for the reduced phytoxicity but the fact that the higher hydrolytic enzyme activity ofP. cinnabarinus, paralleled the decrease of phytotoxicity, indicates that these enzymes seem to be involved. The AM fungusGlomus deserticola increased or exacerbated the beneficial effect of SDOR incubated with saprophytic fungi, in terms of dry weight of tomato plants. The percentage of root length colonized byG. deserticola strongly decreased in presence of DOR, but the level of mycorrhization was higher in presence of ADOR or SDOR. Our results suggest that the combination of aqueous extraction and incubation with saprophytic fungi will open the way for the use of olive oil extraction residues as organic amendment in agricultural soils.

The role of the jasmonate signalling pathway in modulating the establishment of the arbuscular mycorrhiza (AM) symbiosis between tomato plants and Glomus intraradices fungus was studied. The consequences of AM formation due to the blockage of the jasmonate signalling pathway were studied in experiments with plant mutants impaired in JA perception. The tomato jai-1 mutant (jas- monic acid insensitive 1) failed to regulate colonization and was more susceptible to fungal infection, showing acceler- ated colonization. The frequency and the intensity of fungal colonization were greatly increased in the jai-1 insensitive mutant plants. In parallel, the systemic effects on mycorrh- ization due to the activation of the jasmonate signalling pathway by foliar application of MeJA were evaluated and histochemical and molecular parameters of mycorrhizal intensity and efficiency were measured. Histochemical deter- mination of fungal infectivity and fungal alkaline phosphatase activity reveal that the systemic application of MeJA was effective in reducing mycorrhization and mainly affected fungal phosphate metabolism and arbuscule formation, ana- lyzed by the expression of GiALP and the AM-specific gene LePT4, respectively. The results of the present study clearly show that JA participates in the susceptibility of tomato to infection by arbuscular mycorrhizal fungi, and it seems that arbuscular colonization in tomato is tightly controlled by the jasmonate signalling pathway.

We studied the influence of olive mill dry residue (DOR) treated with saprobe fungi on growth of tomato and alfalfa colonized by Glomus deserticola . The application of 25 g kg −1 of dry DOR to soil decreased the shoot and root dry weight of tomato and alfalfa. Plants were more sensitive to the toxicity of DOR when colonized with the arbuscular mycorrhizal (AM) fungi. The sensitivity of both plants to the toxicity of DOR differed according to whether they were colonized by G. deserticola or by indigenous AM fungi. The phytotoxicity of DOR towards tomato and alfalfa was decreased by incubation the residue before planting with saprobe fungi for 20 wk. The beneficial effects of AM fungi on plant growth added with DOR incubated with saprobe fungi depend of the type of the plant and AM fungi. The contribution of AM fungi to the beneficial effect of DOR incubated with saprobe fungi varied according to the type of the plant and AM fungi. G. deserticola increased the shoot and root dry weight of plants when they were grown in the presence of DOR incubated with saprobe fungi for 20 wk. The beneficial effect of saprobe fungi on the dry weight and the level of AM mycorrhization of plants seem to be related to the decrease caused by these fungi in the phenol concentration in DOR. However, the toxicity of DOR due to substances other than phenols can not be ignored. The use of certain saprobe and AM fungi allows the possibility of using DOR as an organic fertilizer.

The present study mainly investigated the ability of solid-state cultures of the non-pathogenic Fusarium oxysporum strain BAFC 738 to transform aromatic components to reduce the phytotoxicity in olive-mill dry residue (DOR), the waste from the two-phase manufacturing process. Lignin, hemicellulose, fats and water-soluble extractives contents of DOR colonized by the fungus for 20 weeks were reduced by 16%, 25%, 71% and 13%, respectively, while the cellulose content increased by 25%. In addition, the ethyl acetate-extractable phenolic fraction of the waste was reduced by 65%. However, mass-balance ultra-filtration and size-exclusion chromatography experiments suggested that the apparent removal of that fraction, mainly including 2-(3,4-dihydroxyphenyl)ethyl alcohol and 2-(4-hydroxyphenyl)ethyl alcohol, was due to polymerization. Mn-peroxidase and Mn-independent peroxidase activities were found in F. oxysporum solid-state cultures, while laccase and aryl alcohol oxidase activities were not detected. Tests performed with seedlings of tomato (Lycopersicum esculentum L.), soybean (Glycine maximum Merr.), and alfalfa (Medicago sativa L.) grown on soils containing 6% (w/w) of bioconverted DOR (kg soil)(-1) showed that the waste's phytotoxicity was removed by 20 weeks-old fungal cultures. By contrast, the same material exhibited a high residual toxicity towards lettuce (Lactuca sativa L.).

No clear data are available on how flavonoids from different chemical groups affect root colonization by arbuscular mycorrhizal fungi (AMF) and whether flavonoids affecting the presymbiotic growth of AMF also affect root colonization by AMF. In the present work, we compared the effect of flavones (chrysin and luteolin) and flavonols (kaempferol, morin, isorhamnetin, and rutin) on root colonization (number of entry points and degree of root colonization) of tomato plants ( Lycopersicum esculentum L.) with the effect of these flavonoids on the presymbiotic growth of these AMF, which has been reported in a recent study. With all tested AMF ( Gigaspora rosea , Gigaspora margarita , Glomus mosseae, and Glomus intraradices) a correlation between the number of entry points and the percentage of root colonization was found. When the number of entry points was high, root colonization was also enhanced. Application of the flavones chrysin and luteolin and of the flavonol morin increased the number of entry points and the degree of colonization,whereas the flavonols kaempferol, isorhamnetin, and rutin showed no effect. These results show that in contrast to their effect on the presymbiotic growth of the AMF on the level of root colonization, the tested flavonoids do not exhibit a genus- and species-specificity. Moreover, comparison of our data with the data obtained by J.M. Scervino, M.A. Ponce, R. Erra-Bassells, H. Vierheilig, J.A. Ocampo, and A. Godeas. (2005a. J. Plant Interact. 15: 22–30) indicates that a positive effect on the hyphal growth of AMF does not necessarily result in an enhanced AM root colonization, further indicating that the mode of action of flavonoids at the level of root colonization is more complex.

The role of abscisic acid (ABA) during the establishment of the arbuscular mycorrhiza (AM) was studied using ABA sitiens tomato (Lycopersicon esculentum) mutants with reduced ABA concentrations. Sitiens plants and wild-type (WT) plants were colonized by Glomus intraradices. Trypan blue and alkaline phosphatase histochemical staining procedures were used to determine both root colonization and fungal efficiency. Exogenous ABA and silver thiosulfate (STS) were applied to establish the role of ABA and putative antagonistic cross-talk between ABA and ethylene during AM formation, respectively. Sitiens plants were less susceptible to the AM fungus than WT plants. Microscopic observations and arbuscule quantification showed differences in arbuscule morphology between WT and sitiens plants. Both ABA and STS increased susceptibility to the AM fungus in WT and sitiens plants. Fungal alkaline phosphate activity in sitiens mutants was completely restored by ABA application. * The results demonstrate that ABA contributes to the susceptibility of tomato to infection by AM fungi, and that it seems to play an important role in the development of the complete arbuscule and its functionality. Ethylene perception is crucial to AM regulation, and the impairment of mycorrhiza development in ABA-deficient plants is at least partly attributable to ethylene.

The mycorrhizal association with the boojum tree, Fouquieria columnaris (=Idria columnaris), was studied. This unusual tree is almost exclusively endemic to granite and volcanic soils in highly arid areas of the Baja California Peninsula of Mexico. Soil and root samples from ten sites, covering the extent of geographic distribution of the tree on the peninsula, were analyzed. The roots of the boojum tree contained all structures of an arbuscular mycorrhizal (AM) association. Morphologically different species, 23 in number, were identified in close vicinity to the boojum tree indicating that F. columnaris is associated with a high number of AM species of several AM genera and families.

Aluminum in acidic conditions is toxic to plants. Aluminum tolerance in some plant species has been ascribed to arbuscular mycorrhizal fungal symbiosis. In this study, the application of aluminum was found to inhibit mycelia development of saprobe fungi Fusarium concolor and Trichoderma koningii and the hyphal length of the arbuscular mycorrhizal fungi Glomus mosseae and Glomus deserticola in vitro. Several levels of aluminum were applied to Eucalyptus globulus plants and inoculated with arbuscular mycorrhizal fungi alone or together with both saprobe fungi. The application of 1,500 mg kg−1 decreased the shoot and root dry weight, chlorophyll content and total P, Mg, and Ca concentrations in the shoot of E. globulus. However, both mycorrhizal fungi G. mosseae and G. deserticola inoculated alone increased the shoot dry weight of Eucalyptus, compared with a non- arbuscular mycorrhizal inoculated control treated with 1,500 mg kg−1 of aluminum. When 1,500 mg kg−1 of aluminum was applied, T. koningii increased the effect of G. deserticola on the shoot weight of eucalyptus, whereas with 3,000 mg kg−1, shoot weight and arbuscular mycorrhizal colonization decreased in all treatments. With 1,500 mg kg−1, the highest accumulation of aluminum in the shoot was obtained when G. deserticola was inoculated together with T. koningii. The possibility of manipulating an arbuscular mycorrhizal inoculation together with a saprobe fungus confers a high aluminum resistance in E. globulus. The effect of such combined inoculation is particularly important in some Chilean volcanic acid soils, mainly those which have been intensively cropped and are without lime addition, which facilitates the increase of phytotoxic aluminum species and limits their agricultural use. Therefore, such dual inoculation in field conditions deserves further investigation. Overall, the arbuscular mycorrhizal and saprobe fungi contribute to the increase in resistance of E. globulus to aluminium.

Dry olive mill residue (DOR) is a solid waste arising from the olive oil two-phase extraction system. The objective of the present study was to investigate the impact of an aerobic treatment of DOR with selected lignin-degrading fungi on both organic matter evolution and residual phytotoxicity of the waste. To this aim, several white-rot fungi, including Phlebia radiata, Coriolopsis rigida, Phanerochaete chrysosporium, Pycnoporus cinnabarinus, Poria subvermispora and Pleurotus pulmonarius were inoculated under axenic conditions for 2 and 20 weeks. The chemical composition and phytotoxicity of DOR were scarcely affected by fungi after 2 weeks incubation. By contrast, both a significant depletion of phenolic compounds and a partial removal of phytoxicity towards Lycopersicum esculentum plants were generally obtained after 20 weeks. The most effective fungus in degrading lignin, total phenols and in removing phytotoxicity was C. rigida. A high correlation was observed between phytotoxicity and phenols added to soil with the waste.

We studied the influence of the laccase activity of two white-rot fungi on the toxic effect of water-soluble substances from dry residues of olives (ADOR) on tomato plants. Pycnoporus cinnabarinus and Coriolopsis rigida decreased the phenol content of ADOR to 73% after 15 days. P. cinnabarinus and C. rigida produced laccase activity after 5 and 15 days, respectively, and the highest activity in both fungi was detected at 20 days. The treatment of ADOR with these white-rot fungi decreased the phytotoxicity of this residue on tomato plants. A close relationship was found between the amount of laccase produced, the decrease in phenol content of ADOR by the saprobic fungi, decrease of phytotoxicity of ADOR, and the increase in dry weight of tomato plants. These results show that phenol removal by the laccase activity of white-rot fungi can be important in the elimination of phytotoxic substances present in olive-mill dry residues.

The effect of different concentrations (0.5, 2 and 8mM) of apigenin and its glycosidated form 5,7,4 0 -hydroxy flavone glycoside on arbuscular mycorrhizal (AM) fungal spore germination, hyphal growth, hyphal branching, the formation of entry points and root colonization of Gigaspora. rosea, Gi. margarita, Glomus mosseae and G. intraradices was tested. The lowest apigenin concentration (0.5mM) nearly doubled hyphal branching, the formation of entry points and root colonization of all four tested fungi, whereas higher concentrations (2 and 8mM) nearly doubled the hyphal growth of Gi. margarita, G. mosseae and G. intraradices. In none of the treatments with the apigenin-glycoside any effect on AM fungi could be observed. Our data show that apigenin exhibits an AM fungal genus and even species activity and we provide strong evidence that glycosidation results in a loss of its activity towards AM fungi. r 2006 Elsevier Ltd. All rights reserved.

Two strains of Gluconacetobacter diazotrophicus (Pal 5, UAP5541) and the arbuscular mycorrhizal fungus Glomus intraradices increased both the shoot and root dry weight of sorghum 45 days after inoculation, whereas they had no effect on the shoot and root dry weight of maize. Co-inoculation (Gluconacetobacter diazotrophicus plus Glomus mosseae) did not increase the shoot and root dry weight of either plant. There was a synergistic effect of Gluconacetobacter diazotrophicus on root colonization of maize by Glomus intraradices, whereas an antagonistic interaction was observed in the sorghum root where the number of Gluconacetobacter diazotrophicus and the colonization by Glomus intraradices were reduced. Plant roots inoculated with Gluconacetobacter diazotrophicus and Glomus intraradices, either separately or together, significantly increased root endoglucanase, endopolymethylgalacturonase and endoxyloglucanase activities. The increase varied according to the plant. For example, in comparison with non-inoculated plants, there were higher endoglucanase (+328%), endopolymethylgalacturonase (+180%) and endoxyloglucanase (+125%) activities in 45-day old co-inoculated maize, but not in 45-day old sorghum. The possibility is discussed that hydrolytic enzyme activities were increased as a result of inoculation with Gluconacetobacter diazotrophicus, considering this to be one of the mechanisms by which these bacteria may increase root colonization by AM fungi.

Primary Sjogren syndrome (PSS) is a chronic autoimmune disease characterized by sicca complex and various systemic manifestations. Although it is well accepted to use corticosteroids for the treatment of systemic manifestations, there is scarce information available regarding the use of targeted therapy for refractory cases. We describe a case of a severe PSS patient refractory to conventional treatment with a response to bortezomib, a proteasome inhibitor commonly used for the treatment of multiple myeloma. Bortezomib administration resulted in a notable improvement of the general symptoms, particularly fatigue, and a decrease in serum globulin levels as well as in serum viscosity. Hyperglobulinemic purpura disappeared, and prednisone tapering succeeded. Because of chronicity, no clinical changes were observed in sicca symptoms. As far as we know, this is the first report on the use of bortezomib in a refractory case of PSS.

The application of Pb inhibited the development of mycelia of the saprobe fungi Fusarium concolor and Trichoderma koningii and the hyphal length of the arbuscular mycorrhizal fungi (AM) Glomus mosseae and G. deserticola in vitro. The application to soil of 1500 mg kg−1 of Pb decreases the dry weight, total N, P, Mg and Fe concentration and chlorophyll content of the shoot of E. globulus no inoculated with AM fungi. However, G. deserticola increased the dry weight, total nutrient concentration and chlorophyll content of the shoot, and the percentage of AM root length colonization and the succinate dehydrogenase activity of AM mycelia of E. globulus in presence of 1500 mg kg−1 of Pb, and these increases were higher when G. deserticola was inoculated together with T. koningii. The application to soil of 3000 mg kg−1 of Pb decreased the shoot dry weight and AM colonization of E. globulus in all treatments tested. Pb was accumulated in the stem more than in the leaves of E. globulus. In presence of 1500 mg kg−1 of Pb the highest accumulation of this metal in the stem took place when E. globulus was colonized with G. deserticola. In conclusion, the possibility to increase Lead accumulation in stem is very attractive for phytoextraction function, the saprobe fungi, AM and their interaction may have a potential role in elevating phytoextraction efficiency and stimulate plant growth under adverse conditions such as lead contaminated soil.

The effect of flavonoids isolated from arbuscular mycorrhizal (AM) colonized and noncolonized clover roots on the number of entry points and percentage of root colonization of tomato (Lycopersicum esculentum L.) by Gigaspora rosea, Gi margarita, Glomus mosseae and G. intrarradices symbionts was determined. With fungi of both genera, a correlation between the number of entry points and the percentage of root colonization was found in the presence of some of the tested flavonoids. The flavonoids acacetin and rhamnetin, present in AM clover roots, inhibited the formation of AM penetration structures and the AM colonization of tomato roots, whereas the flavonoid 5,6,7,8,9-hydroxy chalcone, which could not be detected in AM clover root, inhibited both parameters. The flavonoid quercetin, which was present in AM clover roots, stimulated the penetration and root colonization of tomato by Gigaspora. However, the flavonoids 5,6,7,8-hydroxy-4'-methoxy flavone and 3,5,6,7,4'-hydroxy flavone, which was not found in AM clover root, increased the number of entry points and the AM colonization of tomato roots by Gigaspora. These results indicated that flavonoids could be imnplicated in the process of regulation of AM colonization in plant root, but its role is highly complex and depend not only on flavonoids, but also on AM fungal genus or even species.

The flavonoids 5,6,7,8,9-hydroxy chalcone, 3,7-hydroxy-4′methoxy flavone, 5,6,7,8-hydroxy-4′-methoxy flavone and 3,5,6,7,4′-hydroxy flavone can be detected only in non-mycorrhizal roots of white clover, but not in mycorrhizal roots, whereas the flavonoids acacetin, quercetin and rhamnetin are only present in mycorrhizal roots. We tested the effect of several concentrations of these compounds on spore germination, hyphal growth, hyphal branching, formation of clusters of auxiliary cells and of secondary spores of the arbuscular mycorrhizal fungi Gigaspora rosea, Gigaspora margarita, Glomus mosseae and Glomus intraradices. Our results indicate that depending on the flavonoid, the tested compounds are involved at different stages in the regulation of mycorrhization. This hypothesis is strengthened by their differing effect on several AM fungal growth parameters. Furthermore, our study provides more data on the AM fungus genus/species specificity of flavonoids.

White clover (Trifolium repens) plants were grown in the presence or absence of the arbuscular mycorrhizal fungus Glomus intraradices. Flavones, 4',5,6,7,8-pentahydroxy-3-methoxyflavone and 5,6,7,8-tetrahydroxy-3-methoxyflavone, as well as two flavones 3,7-dihydroxy-4'-methoxyflavone and 5,6,7,8-tetrahydroxy-4'-methoxyflavone never previously reported in plants, were isolated. The known 3,5,6,7,8-pentahydroxy-4'-methoxyflavone, 2',3',4',5',6'-pentahydroxy-chalcone, 6-hydroxykaempferol, 4',5,6,7,8-pentahydroxyflavone and 3,4'-dimethoxykaempferol were also obtained. Analysis of extracts obtained from roots and shoots revealed that the compositions of the flavonoid mixtures varied with growing conditions. Quercetin, acacetin and rhamnetin accumulated in roots of inoculated plants, whereas they were not detected in non-inoculated plants.

We studied the influence of dry olive mill residue (DOR), as affected by saprobic fungi on the growth of soybean ( Glycine max ) and tomato ( Lycopersicum esculentum ). The application of 60 g kg −1 of DOR decreased the dry weight of tomato and soybean plants mainly because of its phenolic content. The phytotoxicity of DOR decreased when it was incubated in the presence of almost all of the saprobic fungi tested. All saprobic fungi tested in our experiments were able to decrease the phenol content of DOR, and a correlation between the decrease in the phenol content of DOR by saprobic fungi and the increase in the dry weight of plants was found. However, the toxicity of these residues to either tomato or soybean plants did not decrease in the presence of all saprobic fungi in spite of a decrease in phenolic compounds. Some of the saprobic fungi tested eliminate completely the phytotoxicity of DOR. F. oxysporum 738 and F. lateritum were capable of transforming the DOR, after incubation for 20 weeks, so that the tomato plants to which this transformed DOR was applied increased significantly in shoot dry weight compared with the tomato plants which did not receive DOR. These results open the possibility of the use of DOR as organic fertilizer.

The interaction between Trichoderma pseudokoningii (Rifai) 511, 2212, 741A, 741B and 453 and the arbuscular mycorrhizal fungi Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe BEG12 and Gigaspora rosea Nicolson & Schenck BEG9 were studied in vitro and in greenhouse experiments. All T. pseudokoningii strains inhibited the germination of G. mosseae and Gi. rosea except the strain 453, which did not affect the germination of Gi. rosea. Soluble exudates and volatile substances produced by all T. pseudokoningii strains inhibited the spore germination of G. mosseae. The germination of Gi. rosea spores was inhibited by the soluble exudates produced by T. pseudokoningii 2212 and 511, whereas T. pseudokoningii 714A and 714B inhibited the germination of Gi. rosea spores by the production of volatile substances. The strains of T. pseudokoningii did not affect dry matter and percentage of root length colonization of soybean inoculated with G. mosseae, except T. pseudokoningii 2212, which inhibited both parameters. However, all T. pseudokoningii strains decreased the shoot dry matter and the percentage of AM root length colonization of soybean inoculated with Gi. rosea. The saprotrophic fungi tested seem to affect AM colonization of root by effects on the presymbiotic phase of the AM fungi. No influence of AM fungi on the number of CPUs of T. pseudokoningii was found. The effect of saprotrophic fungi on AM fungal development and function varied with the strain of the saprotrophic species tested. Fil: Martinez, Alicia Elba. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; Argentina Fil: Obertello, Mariana. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pardo, Alejandro Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina Fil: Ocampo, Juan A.. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; España Fil: Godeas, Alicia Margarita. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Multidrug resistance-1 (MDR-1) is characterized by overfunction of P-glycoprotein (P-gp), a pump molecule that decreases intracellular drug concentration by effluxing them from the intracellular space. Broad ranges of structurally unrelated compounds are transported by P-gp, including antineoplastic agents, HIV protease inhibitors, prednisone, gold salts, methotrexate, colchicine as well as several antibiotics. In contrast, many other compounds such as calcium channel blockers (verapamil) and immunosupressors (cyclosporine-A) are able to inhibit P-gp function. The P-gp role in therapeutic failures has been extensively studied in cancer; however, there is little information regarding MDR-1 phenotype in autoimmune disorders. It has been reported that an increased number of lymphocytes are able to extrude P-gp substrates in rheumatoid arthritis, immune thrombocytopenic purpura and systemic lupus erythematosus, the patients with poor response to treatment being the ones that exhibit the highest values. This may be due, at least in part, to a simultaneous long-term usage of several drugs that induce P-gp function. Since abnormally activated cell compartments characterize autoimmune diseases, it is possible that those cells are the ones that exhibit drug resistance. The study of drug resistance mechanisms in autoimmunity may be helpful for the optimization of the current therapeutic schemes through their combination with low doses of P-gp inhibitors.

Wild type, transgenic NahG tobacco plants with reduced levels of salicylic acid (SA) and transgenic CSA (constitutive SA biosynthesis) tobacco plants with enhanced SA levels were inoculated with the arbuscular mycorrhizal fungi (AMF) Glomus mosseae or Glomus intraradices. In a time course study the effect of SA content on root colonization by the fungal symbiont was determined. Throughout the experiment in NahG plants an enhanced root colonization level could be detected, whereas in CSA plants mycorrhization was reduced. At the end of the experiment with Glomus mosseae, root colonization was similar in wild type and in transgenic plants (NahG and CSA plants), indicating that enhanced SA levels in plants can have an effect on delay AMF root colonization, but do not affect the symbiotic potential of plants in terms of changes in maximal threshold of root colonization. Compared to non-mycorrhizal plants, in mycorrhizal wild type and NahG the SA concentration was reduced. The role of SA in the regulation of mycorrhization is discussed.

The effect of the soil yeast, Rhodotorula mucilaginosa LBA, on Glomus mosseae (BEG n°12) and Gigaspora rosea (BEG n°9) was studied in vitro and in greenhouse trials. Hyphal length of G. mosseae and G. rosea spores increased significantly in the presence of R. mucilaginosa. Exudates from R. mucilaginosa stimulated hyphal growth of G. mosseae and G. rosea spores. Increase in hyphal length of G. mosseae coincided with an increase in R. mucilaginosa exudates. No stimulation of G. rosea hyphal growth was detected when 0.3 and 0.5 ml per petri dish of yeast exudates was applied. Percentage root length colonization by G. mosseae in soybean (Glycine max L. Merill) and by G. rosea in red clover (Trifolium pratense L. cv. Huia) was increased only when the soil yeast was inoculated before G. mosseae or G. rosea was introduced. Beneficial effects of R. mucilaginosa on arbuscular mycorrhizal (AM) colonization were found when the soil yeast was inoculated either as a thin agar slice or as a volume of 5 and 10 ml of an aqueous solution. R. mucilaginosa exudates (20 ml per pots) applied to soil increased significantly the percentage of AM colonization of soybean and red clover.

We studied the influence of olive mill dry residue (DOR) on growth of soybean (Glycine max ) and lettuce (Lactuca sativa ) colonized with the arbuscular fungi Glomus mosseae or G. deserticola. The DOR has 6 mg g 21 of soluble phenolic compounds and the application of 2.5 g kg 21 of DOR (15 mg kg 21 of phenolic content) to soil decreased the growth of plants colonized with the AM fungi. The application to the soil of 10 g kg 21 of DOR (60 mg kg 21 of phenolic content) decreased the dry weight of nonarbuscular mycorrhizal (AM) plants. The application of DOR decreased the percentage of AM colonization of plants except those were inoculated with G. mosseae or G. deserticola 4 weeks before the application of DOR. No effect of the residue on the colonization of these previously AM inoculated plants was observed. DOR had no effect neither on the fungal succinate dehydrogenase activity nor on the most probable number of AM propagules in all treated soils. The obtained results showed than AM fungi increased the phytotoxicity of DOR in lettuce and soybean. q 2002 Elsevier Science Ltd. All rights reserved.

The response of plants to arbuscular mycorrhizal fungi involves a temporal and spatial activation of different defence mechanisms. The activation and regulation of these defences have been proposed to play a role in the maintenance of the mutualistic status of the association, however, how these defences affect the functioning and development of arbuscular mycorrhiza remains unclear. A number of regulatory mechanisms of plant defence response have been described during the establishment of the arbuscular mycorrhizal symbiosis, including elicitor degradation, modulation of second messenger concentration, nutritional and hormonal plant defence regulation, and activation of regulatory symbiotic gene expression. The functional characterization of these regulatory mechanisms on arbuscular mycorrhiza, including cross-talk between them, will be the aim and objective of future work on this topic.

Resume Objectif. Ce travail a eu pour but d’evaluer l’efficacite therapeutique du leflunomide, prescrit en une prise hebdomadaire de 100 mg, chez des patients atteints de polyarthrite rhumatoide refractaire. Methodes. Les 16 patients inclus dans cette etude etaient âges de 18 a 72 ans et etaient atteints d’une polyarthrite rhumatoide evoluant depuis 2 a 32 ans. Huit patients ont ete traites par le leflunomide a la posologie d’une prise hebdomadaire de 100 mg et huit patients ont ete traites par le leflunomide selon les modalites conventionnelles comportant une prise quotidienne. Tous les patients ont ete evalues chaque mois pendant une annee. Nous avons utilise les criteres de reponse de l’ACR 1995 pour la polyarthrite rhumatoide. Resultats. Apres deux mois de traitement, il a ete observe une importante amelioration dans le groupe traite par leflunomide de maniere classique : sept des huit patients repondaient aux criteres ACR 20. En revanche, l’amelioration etait moins evidente dans le groupe traite par leflunomide hebdomadaire : trois des huit patients etaient repondeurs aux criteres ACR 20. Apres une periode de quatre a six mois, la reponse etait similaire entre les deux groupes ; une reponse ACR 50 etait observee chez les six patients traites de maniere quotidienne et chez six des huit patients traites de maniere hebdomadaire. Ce resultat a persiste jusqu’a la fin de l’etude. Il n’a pas ete observe de difference statistiquement significative entre les deux groupes et ce quel que soit le parametre etudie. Des effets indesirables sont survenus chez six des huit patients traites par le leflunomide de maniere quotidienne et deux de ces patients ont ete obliges d’arreter le leflunomide, l’un pour des signes gastro-intestinaux severes et l’autre pour une toxicite hepatique. Dans le groupe traite par le leflunomide hebdomadaire, deux patients ont eu des effets indesirables qui ont spontanement regresse. Conclusion. L’utilisation du leflunomide sous la forme d’une prise hebdomadaire de 100 mg permet d’obtenir un effet therapeutique similaire a celui du schema therapeutique conventionnel et pourrait representer une nouvelle option therapeutique dans la polyarthrite rhumatoide refractaire.

Aims. To assess the therapeutic effect of leflunomide in weekly dose of 100 mg in patients with refractory rheumatoid arthritis. Material and Methods. Sixteen patients were included (18-72 years, disease duration 2-32 years). Eight patients received a weekly dose of 100 mg of leflunomide and 8 the conventional dose. Current treatment was not modified. All patients underwent a monthly evaluation for one year, applying the 1995 ACR preliminary definition of improvement in rheumatoid arthritis. Results. After 2 months, the group treated with the conventional leflunomide dose evidenced a remarkable improvement (7/8 patients achieving ACR 20), while the group receiving the weekly dose, the improvement was not as clearly evident (3/8 patients achieving ACR 20). By the fourth to sixth month, the response was comparable on both groups (6/6 and 6/8 patients achieving ACR 50 in the daily and weekly dose, respectively) and prevailed through the end of the study. There were no statistical differences between groups at any evaluation. Side effects made itself clear in 6 patients in the daily leflunomide group, and 2 patients withdrawn leflunomide because severe gastrointestinal symptoms and hepatotoxicity, respectively. In the group of weekly leflunomide 2 patients presented side effects which disappeared spontaneously. Conclusion. The use of leflunomide in a weekly dose of 100 mg proved to have similar therapeutic benefit as that of the conventional scheme and might represent a new option for the treatment of refractory rheumatoid arthritis patients.

Convective drying is a conventional method to prolong the shelf-life of foods that could negatively affect the product quality due to the long exposure time to high temperature. Ultrasound (US) has been used for reducing the drying time while maintaining the product quality. In this study a Box-Behnken design of Response Surface Methodology (RSM) was used to evaluate the effects of US time-frequency (t), US power level (Pot), and hot air temperature (T) on the drying process time (DPT), apparent density (AD), and color difference (ΔE) of the dried mango slices (10.0 ± 1.0% wet basis). Fisher's statistical testing was performed for the analysis of variance (ANOVA) for quadratic regression equations. The optimization goals were to minimize the responses. Modeled optimized conditions were 52–55 °C, 45–60 W, and 3 min/30 min for T, Pot, and t, respectively. Energy consumption and carbon footprint were also estimated during the validation of the optimal drying conditions. Practical applications: This research explored the use of response surface methodology polynomial models fitted to the experimental data of US assisted drying assays to find the best values of air temperature, time-frequency, and power of sonication for minimization of the drying process time (DPT) apparent density, and color difference of mango slices. The results specified ranges for the input-variables where lower DPT and properly dried mango quality parameters co-exist with important reductions in operational costs and carbon foot-print compared with those estimated for conventional dehydration process. These findings are of interest toward the development of greener and more sustainable food drying processes. © 2017 Wiley Periodicals, Inc. The authors acknowledge the financial support of the FONTAGRO (Project FTG/RF-1330-RG) and UNIVERSIDAD NACIONAL DE COLOMBIA (Project HERMES 34573).

This multi-case study paper analyses the influence of both nationalisation and privatisation patterns on five major Latin American oil companies: Petrobras, PEMEX, PDVSA, Ecopetrol and YPF. The paper uses case study methodology in which each case was studied individually to identify unique case features, and to eventually conduct a cross-case analysis in which patterns are studied. Data was collected from publicly available secondary sources. After a careful examination and analysis of the selected cases, it can be concluded that semi-privatised Latin American oil companies directly compete with private companies in terms of revenues, growth and international presence. Based on analysis and comparisons, this study concludes that private participation might have had a positive effect in Latin American oil companies internationally.

We studied the possibility that the antagonistic saprobe fungi Coriolopsis rigida, Trametes versicolor, Fusarium lateritium, Penicillium chrysogenum and Verticillium dahliae-2379 may control V. dahliae disease through the inhibition of the activity of hydrolytic enzymes produced by the pathogen. These saprobe fungi were able to decrease the growth in vitro of V. dahliae. The exudates produced by these fungi seemed to be the main factor responsible for their antagonistic effect. The exudates of all the fungi tested had endopolymethylgalacturonase, endoglucanase and endoxyloglucanase activities. Exudates of P. chrysogenum and V. dahliae-2379 had higher hydrolytic activities than those of V. dahliae. The saprobe V. dahliae-2379 did not decrease the growth of the pathogen V. dahliae but decreased its harmful effect on the growth of tomato. However, no inhibition of the activities of the hydrolytic enzyme of the pathogenic V. dahliae by the no pathogenic V. dahliae-2379 or by the other saprobe fungi was observed. Nevertheless, the protection of tomato by the five antagonistic saprobe fungi against V. dahliae disease could be carried out by the induction of plant defense by the hydrolytic enzymes produced by these fungi.

© 2014 Scandinavian Plant Physiology Society. Gibberellins (GAs) are key regulators of plant growth and development and recent studies suggest also a role during arbuscular mycorrhizal (AM) formation. Here, complementary approaches have been used to obtain a clearer picture that correlates AM fungal development inside roots with GA metabolism. An extensive analysis of genes associated with GA metabolism as well as a quantification of GA content in roots was made. Application of GA3 and its biosynthesis inhibitor prohexadione calcium (PrCa) combined with a GA-constitutive response mutant (procera) were used to determine whether fungal colonization is altered by the level of these hormones or by changes in the GA-signaling pathway. The increased levels of specific GAs from the 13-hydroxylation pathway in mycorrhizal roots correlate closely with the increased expression of genes coding enzymes from the GA biosynthetic trail. The imbalance of GAs in tomato roots caused by exogenous applications of GA3 or PrCa affects arbuscules in both negative and positive ways, respectively. In addition, procera plants were adversely affected by the mycorrhization process. Our findings demonstrate that an imbalance in favor of an increased amount of GAs negatively affects the frequency of mycorrhization and particularly the arbuscular abundance in tomato mycorrhizal roots and the results point out that AM formation is associated with a change in the 13-hydroxylation pathway of GAs., We wish to thank the Tomato Genet- ics Resource Centre (TGRC) of the University of California for providing tomato seeds. We would also like to thank Isabel Tamayo for her help with the plant experiments and Michael O’Shea for proof-reading the document. Financial support for this study was provided by grants from the Comisión Interministerial de Ciencia y Teconlogía (CICYT) and Fondos Europeos de Desarrollo Regional (FEDER) through the Ministerio de Economía y Competitividad in Spain (AGL2008-00742; AGL2011-25930) as well as the Junta de Andalucía (Research Group BIO 260). JA Martín Rodríguez was supported by fellowships under the FPU-MICINN program. The authors also acknowledge financial support of Ministry of Education, Youth and Sports of the Czech Republic (LK21306), EU funding from the Operational Program Research and Development for Innovations (ED0007/01/01) and Internal Grant Agency of Palack y University (PrF_2013_023).