143 research outputs found
The specific expression of isoperoxidases in grapevine cells cultured in suspension in relation to vacuolar development
Die spezifischen Veränderungen der Isoperoxidasen in suspensionskultivierten Rebenzellen in Beziehung zur Entwicklung der ZellvakuoleAus wachsenden Beeren der Rotweinsorte Gamay (Vitis vinifera) wurden Zellsuspensionskulturen hergestellt. Diese dienten als Modellsystem, um die spezifischen Veränderungen der Enzymaktivität von Guajakol-Peroxidase und Indolyl-3-Essigsäure(IAA-)Oxidase während des Zellwachstums in Beziehung zur Entwicklung der Zellvakuole zu verfolgen. Der Entwicklungszustand der Vakuole wurde anhand des Verhältnisses monomere Anthocyane : Protein festgestellt. Die Untersuchungen zeigten, daß sich die Aktivität von Guajakol-Peroxidase während der exponentiellen Phase des Zellwachstums in Beziehung zum Entwicklungszustand der Vakuole veränderte. Andererseits wurde im Verlauf des Zellwachstums nie IAA-Oxidaseaktivität nachgewiesen, wahrscheinlich weil in den kultivierten Zellen höhere Konzentrationen von "Auxinprotektoren" vorhanden waren.Dieser Befund steht im Widerspruch zu der Beobachtung, daß die Zunahme der Gesamtperoxidasenaktivität in den Zellen in erster Linie auf den Anstieg der basischen Isoperoxidasen zurückzuführen ist. Aufgrund der Tatsache, daß der IAA-Abbau hauptsächlich durch basische Isoperoxidasen bewirkt wird, wird ferner die anerkannte physiologische Rolle der basischen Isoperoxidasen in suspensionskultivierten Zellen in Frage gestellt. Eine alternative Rolle, welche die basischen Isoperoxidasen im intensiven oxidativen Stoffwechsel der Phenole bei roten Rebsorten spielen könnten, wird diskutiert
Caracterización de morteros con cerámica reciclada y su uso en piezas prefabicadas para entrevigado de forjados
This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate.
The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.Este trabajo analiza morteros con diferentes porcentajes de cerámica reciclada como sustituto parcial de la arena. Además el estudio examina las propiedades físicas, químicas y mecánicas de los nuevos morteros, empleando diferentes porcentajes de sustitución (10% - 50%). Con anterioridad, se caracterizaron todos los materiales empleados en este trabajo mediante difracción y fluorescencia de rayos-X. El objetivo fue determinar las diferencias y similitudes en la composición química y mineralógica de los distintos tipos de residuos cerámicos y del resto de áridos utilizados.
Los resultados muestran que es posible obtener morteros con menor densidad frente a las muestras sin contenido reciclado. Sus características los hacen idóneos para la creación de piezas prefabricadas de entrevigado para rehabilitación de forjados. Finalmente. Las piezas se usaron en un caso de estudio real, destacando las ventajas estructurales que conlleva su uso
Synergistic effect of methyljasmonate and cyclodextrin on stilbene biosynthesis pathway gene expression and resveratrol production in Monastrell grapevine cell cultures
<p>Abstract</p> <p>Background</p> <p>Plant cell cultures have been shown as feasible systems for the production of secondary metabolites, being the elicitation with biotic or abiotic stimuli the most efficient strategy to increase the production of those metabolites. Vitaceae phytoalexins constitute a group of molecules belonging to the stilbene family which are derivatives of the <it>trans</it>-resveratrol structure and are produced by plants and cell cultures as a response to biotic and abiotic stresses. The potential benefits of resveratrol on human health have made it one of the most thoroughly studied phytochemical molecules. The aim of this study was to evaluate the elicitor effect of both cyclodextrin (CD) and methyljasmonate (MeJA) on grapevine cell cultures by carrying out a quantitative analysis of their role on resveratrol production and on the expression of stilbene biosynthetic genes in <it>Vitis vinifera </it>cv Monastrell albino cell suspension cultures.</p> <p>Findings</p> <p>MeJA and CD significantly but transiently induced the expression of stilbene biosynthetic genes when independently used to treat grapevine cells. This expression correlated with resveratrol production in CD-treated cells but not in MeJA-treated cells, which growth was drastically affected. In the combined treatment of CD and MeJA cell growth was similarly affected, however resveratrol production was almost one order of magnitude higher, in correlation with maximum expression values for stilbene biosynthetic genes.</p> <p>Conclusion</p> <p>The effect of MeJA on cell division combined with a true and strong elicitor like CD could be responsible for the observed synergistic effect of both compounds on resveratrol production and on the expression of genes in the stilbene pathway.</p
A reliable protocol for the stable transformation of non-embryogenic cells cultures of grapevine (Vitis vinifera L.) and Taxus x media
One of the major intent of metabolic engineering in cell culture systems is to increase yields of secondary metabolites. Efficient transformation methods are a priority to successfully apply metabolic engineering to cell cultures of plants that produce bioactive or therapeutic compounds, such as Vitis vinifera and Taxus x media. The aim of this study was to establish a reliable method to transform non-embryogenic cell cultures of these species. The V. vinifera cv. Gamay/cv. Monastrell cell lines and Taxus x media were used for Agrobacterium-mediated transformation using the Gateway-compatible Agrobacterium sp. binary vector system for fast reliable DNA cloning. The Taxus x media and Vitis cell lines were maintained in culture for more than 4 and 15 months, respectively, with no loss of reporter gene expression or antibiotic resistance. The introduced genes had no discernible effect on cell growth, or led to extracellular accumulation of phytoalexin trans-Resveratrol (t-R) in response to elicitation with methylated cyclodextrins (MBCD) and methyl jasmonate (MeJA) in the grapevine transgenic cell lines compared to the parental control. The method described herein provides an excellent tool to exploit exponentially growing genomic resources to enhance, optimize or diversify the production of bioactive compounds generated by grapevine and yew cell cultures, and offers a better understanding of many grapevine and yew biology areas.This work has been supported by grants from the Spanish Ministry of Science and Innovation (BIO2011-29856-C02-01, BIO2011-29856-C02-02 and BIO2014-51861-R), European Funds for Regional Development (FEDER) and Conselleria d’Educacio, Cultura i Sport de la Generalitat Valenciana (FPA/2013/A/074). J.M.C. holds a postdoctoral grant from SENESCYT-GOVERNMENT OF ECUADOR (006-IECESMG5-GPLR-2012)
Serotonergic Polymorphisms and Psychotic Disorders in Populations From North Spain
There is strong biological evidence relating alterations in the serotonergic
system with mental disorders. These alterations may be originated at the DNA
level by sequence mutations that alter the functioning of serotonin receptors and
transporter. To test this hypothesis we investigated three genetic variants of
the 5-HT2A receptor (-1438G/A, 102T/C and His452Tyr) and two variants of the
serotonin transporter (a VNTR in the second intron and a 44 bp insertion/delition
in the promoter region of the gene) in a clinical sample recruited in a human
isolate and in surrounding areas in Northern Spain (N = 257) and in ethnically
matched controls (N = 334). No clear association was found between 5-HT2A
variants and psychosis. However, marginal associations were observed between the
5-HTT LPR and VNTR variants and psychosis (P < or = 0.05) indicating a minor
contribution to psychosis of genetic alterations in this gene
Meta-analysis of functional neuroimaging and cognitive control studies in schizophrenia: preliminary elucidation of a core dysfunctional timing network
Timing and other cognitive processes demanding cognitive control become interlinked
when there is an increase in the level of difficulty or effort required. Both functions are
interrelated and share neuroanatomical bases. A previous meta-analysis of neuroimaging
studies found that people with schizophrenia had significantly lower activation, relative
to normal controls, of most right hemisphere regions of the time circuit. This finding
suggests that a pattern of disconnectivity of this circuit, particularly in the supplementary
motor area, is a trait of this mental disease. We hypothesize that a dysfunctional
temporal/cognitive control network underlies both cognitive and psychiatric symptoms of
schizophrenia and that timing dysfunction is at the root of the cognitive deficits observed.
The goal of our study was to look, in schizophrenia patients, for brain structures activated
both by execution of cognitive tasks requiring increased effort and by performance of time
perception tasks. We conducted a signed differential mapping (SDM) meta-analysis of
functional neuroimaging studies in schizophrenia patients assessing the brain response
to increasing levels of cognitive difficulty. Then, we performed a multimodal meta-analysis
to identify common brain regions in the findings of that SDM meta-analysis and our
previously-published activation likelihood estimate (ALE) meta-analysis of neuroimaging
of time perception in schizophrenia patients. The current study supports the hypothesis
that there exists an overlap between neural structures engaged by both timing tasks and
non-temporal cognitive tasks of escalating difficulty in schizophrenia. The implication is
that a deficit in timing can be considered as a trait marker of the schizophrenia cognitive
profile
Fetal Demise and Failed Antibody Therapy During Zika Virus Infection of Pregnant Macaques
Zika virus (ZIKV) infection of pregnant women is associated with pathologic complications of fetal development. Here, we infect pregnant rhesus macaques (Macaca mulatta) with a minimally passaged ZIKV isolate from Rio de Janeiro, where a high rate of fetal development complications was observed. The infection of pregnant macaques with this virus results in maternal viremia, virus crossing into the amniotic fluid (AF), and in utero fetal deaths. We also treated three additional ZIKV-infected pregnant macaques with a cocktail of ZIKV-neutralizing human monoclonal antibodies (nmAbs) at peak viremia. While the nmAbs can be effective in clearing the virus from the maternal sera of treated monkeys, it is not sufficient to clear ZIKV from AF. Our report suggests that ZIKV from Brazil causes fetal demise in non-human primates (NHPs) without additional mutations or confounding co-factors. Treatment with a neutralizing anti-ZIKV nmAb cocktail is insufficient to fully stop vertical transmission
Multicenter study of brain volume abnormalities in children and adolescent-onset psychosis
The goal of the study is to determine the extent of structural brain abnormalities in a multicenter sample of children and adolescents with a recent-onset first episode of psychosis (FEP), compared with a sample of healthy controls. Total brain and lobar volumes and those of gray matter (GM), white matter, and cerebrospinal fluid (CSF) were measured in 92 patients with a FEP and in 94 controls, matched for age, gender, and years of education. Male patients (n = 64) showed several significant differences when compared with controls (n = 61). GM volume in male patients was reduced in the whole brain and in frontal and parietal lobes compared with controls. Total CSF volume and frontal, temporal, and right parietal CSF volumes were also increased in male patients. Within patients, those with a further diagnosis of "schizophrenia" or "other psychosis" showed a pattern similar to the group of all patients relative to controls. However, bipolar patients showed fewer differences relative to controls. In female patients, only the schizophrenia group showed differences relative to controls, in frontal CSF. GM deficit in male patients with a first episode correlated with negative symptoms. Our study suggests that at least part of the GM deficit in children and adolescent-onset schizophrenia and in other psychosis occurs before onset of the first positive symptoms and that, contrary to what has been shown in children-onset schizophrenia, frontal GM deficits are probably present from the first appearance of positive symptoms in children and adolescents
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