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1.
Psychol Health Med ; 28(7): 1873-1882, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35635262

RESUMEN

Despite the known association of chronic cardiovascular diseases and more severe courses of COVID-19, little is known about individual risk perception of patients with a history of acute myocardial infarction (AMI) and resulting preventive behaviours. In May 2020, a postal survey was conducted, including 150 patients with previous AMI from the myocardial infarction registry Augsburg. The study objective was to assess COVID-19 knowledge, individual risk perception, worries, infection likelihood and preventive behaviours in this patient cohort. From the 100 respondents, 69.7% perceived themselves to be at high risk of developing a severe course of COVID-19. There was a significant positive correlation between dangerousness assessment and knowledge on COVID-19. Despite a majority (70%) of patients rating their susceptibility for an infection as moderate to very high, the individual likelihood of being infected was rated at only 3%. Almost 70% of patients with previous MI classified themselves at high risk for a severe course of COVID-19 infection. As seen in other risk groups as well, the availability of valuable information sources as well as the support in individual risk reduction strategies and psychological coping mechanisms are mandatory, especially since higher knowledge correlates with dangerousness assessment and might lead to better compliance with preventive behaviours.

3.
Cochrane Database Syst Rev ; 11: CD004293, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34778952

RESUMEN

BACKGROUND: Primary membranous nephropathy (PMN) is a common cause of nephrotic syndrome in adults. Without treatment, approximately 30% of patients will experience spontaneous remission and one third will have persistent proteinuria. Approximately one-third of patients progress toward end-stage kidney disease (ESKD) within 10 years. Immunosuppressive treatment aims to protect kidney function and is recommended for patients who do not show improvement of proteinuria by supportive therapy, and for patients with severe nephrotic syndrome at presentation due to the high risk of developing ESKD. The efficacy and safety of different immunosuppressive regimens are unclear. This is an update of a Cochrane review, first published in 2004 and updated in 2013. OBJECTIVES: The aim was to evaluate the safety and efficacy of different immunosuppressive treatments for adult patients with PMN and nephrotic syndrome. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 1 April 2021 with support from the Cochrane Kidney and Transplant Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials (RCTs) investigating effects of immunosuppression in adults with PMN and nephrotic syndrome were included. DATA COLLECTION AND ANALYSIS: Study selection, data extraction, quality assessment, and data synthesis were performed using Cochrane-recommended methods. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: Sixty-five studies (3807 patients) were included. Most studies exhibited a high risk of bias for the domains, blinding of study personnel, participants and outcome assessors, and most studies were judged unclear for randomisation sequence generation and allocation concealment. Immunosuppressive treatment versus placebo/no treatment/non-immunosuppressive treatment In moderate certainty evidence, immunosuppressive treatment probably makes little or no difference to death, probably reduces the overall risk of ESKD (16 studies, 944 participants: RR 0.59, 95% CI 0.35 to 0.99; I² = 22%), probably increases total remission (complete and partial) (6 studies, 879 participants: RR 1.44, 95% CI 1.05 to 1.97; I² = 73%) and complete remission (16 studies, 879 participants: RR 1.70, 95% CI 1.05 to 2.75; I² = 43%), and probably decreases the number with doubling of serum creatinine (SCr) (9 studies, 447 participants: RR 0.46, 95% CI 0.26 to 0.80; I² = 21%). However, immunosuppressive treatment may increase the number of patients relapsing after complete or partial remission (3 studies, 148 participants): RR 1.73, 95% CI 1.05 to 2.86; I² = 0%) and may lead to a greater number experiencing temporary or permanent discontinuation/hospitalisation due to adverse events (18 studies, 927 participants: RR 5.33, 95% CI 2.19 to 12.98; I² = 0%). Immunosuppressive treatment has uncertain effects on infection and malignancy. Oral alkylating agents with or without steroids versus placebo/no treatment/steroids Oral alkylating agents with or without steroids had uncertain effects on death but may reduce the overall risk of ESKD (9 studies, 537 participants: RR 0.42, 95% CI 0.24 to 0.74; I² = 0%; low certainty evidence). Total (9 studies, 468 participants: RR 1.37, 95% CI 1.04 to 1.82; I² = 70%) and complete remission (8 studies, 432 participants: RR 2.12, 95% CI 1.33 to 3.38; I² = 37%) may increase, but had uncertain effects on the number of patients relapsing, and decreasing the number with doubling of SCr. Alkylating agents may be associated with a higher rate of adverse events leading to discontinuation or hospitalisation (8 studies 439 participants: RR 6.82, 95% CI 2.24 to 20.71; I² = 0%). Oral alkylating agents with or without steroids had uncertain effects on infection and malignancy. Calcineurin inhibitors (CNI) with or without steroids versus placebo/no treatment/supportive therapy/steroids We are uncertain whether CNI with or without steroids increased or decreased the risk of death or ESKD, increased or decreased total or complete remission, or reduced relapse after complete or partial remission (low to very low certainty evidence). CNI also had uncertain effects on decreasing the number with a doubling of SCr, temporary or permanent discontinuation or hospitalisation due to adverse events, infection, or malignancy. Calcineurin inhibitors (CNI) with or without steroids versus alkylating agents with or without steroids We are uncertain whether CNI with or without steroids increases or decreases the risk of death or ESKD. CNI with or without steroids may make little or no difference to total remission (10 studies, 538 participants: RR 1.01, 95% CI 0.89 to 1.15; I² = 53%; moderate certainty evidence) or complete remission (10 studies, 538 participants: RR 1.15, 95% CI 0.84 to 1.56; I² = 56%; low certainty evidence). CNI with or without steroids may increase relapse after complete or partial remission. CNI with or without steroids had uncertain effects on SCr increase, adverse events, infection, and malignancy. Other immunosuppressive treatments Other interventions included azathioprine, mizoribine, adrenocorticotropic hormone, traditional Chinese medicines, and monoclonal antibodies such as rituximab. There were insufficient data to draw conclusions on these treatments. AUTHORS' CONCLUSIONS: This updated review strengthened the evidence that immunosuppressive therapy is probably superior to non-immunosuppressive therapy in inducing remission and reducing the number of patients that progress to ESKD. However, these benefits need to be balanced against the side effects of immunosuppressive drugs. The number of included studies with high-quality design was relatively small and most studies did not have adequate follow-up. Clinicians should inform their patients of the lack of high-quality evidence. An alkylating agent (cyclophosphamide or chlorambucil) combined with a corticosteroid regimen had short- and long-term benefits, but this was associated with a higher rate of adverse events. CNI (tacrolimus and cyclosporin) showed equivalency with alkylating agents however, the certainty of this evidence remains low. Novel immunosuppressive treatments with the biologic rituximab or use of adrenocorticotropic hormone require further investigation and validation in large and high-quality RCTs.


Asunto(s)
Glomerulonefritis Membranosa , Síndrome Nefrótico , Azatioprina , Ciclosporina , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/tratamiento farmacológico , Humanos , Inmunosupresores/efectos adversos , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/tratamiento farmacológico
4.
Sci Rep ; 9(1): 17201, 2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31748672

RESUMEN

Lepidoptera have little fossilization potential due to the presence of delicate structures and hence are exceptional findings, even in ambers that allow their preservation in sufficient detail for interpretation. From Eocene Baltic amber, the volumetrically largest known deposit of amber, there has been no reliable report of any member of the Macrolepidoptera (informal group of higher moths and all butterflies). Any such lepidopteran fossil would provide insight into evolutionary processes during the Eocene, long after flowering plants had completed their initial radiation. Here, we report on a first geometrid caterpillar from Baltic amber which is described as the oldest evidence for the subfamily Ennominae (tribe Boarmiini) and as one of the oldest records of the currently mega-diverse family. The new finding provides an important calibration point for molecular clock analyses within the family Geometridae and predates the basal divergence of Boarmiini from 32-38 to 44 Mya. It also predates the occurrence of this highly specialized form of caterpillar locomotion that allows for rapid movement.

5.
J Agric Food Chem ; 65(17): 3559-3568, 2017 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-28409937

RESUMEN

Flavonoids are important metabolites in strawberries (Fragaria × ananassa) because they accomplish an extensive collection of physiological functions and are valuable for human health. However, their localization within the fruit tissue has not been extensively explored. Matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI) was employed to shed light on the spatial distribution of flavonoids during fruit development. One wild-type (WT) and two transgenic lines were compared, wherein the transgenic enzymes anthocyanidin reductase (ANRi) and flavonol synthase (FLSi), respectively, were down-regulated using an RNAi-based silencing approach. In most cases, fruit development led to a reduction of the investigated flavonoids in the fruit tissue; as a consequence, they were exclusively present in the skin of mature red fruits. In the case of (epi)catechin dimer, both the ANRi and the WT phenotypes revealed low levels in mature red fruits, whereas the ANRi line bore the lowest relative concentration, as analyzed by liquid chromatography-electrospray ionization multiple-step mass spectrometry (LC-ESI-MSn).


Asunto(s)
Flavonoides/metabolismo , Fragaria/metabolismo , Frutas/química , Flavonoides/química , Fragaria/química , Fragaria/genética , Fragaria/crecimiento & desarrollo , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Estructura Molecular , NADH NADPH Oxidorreductasas/genética , NADH NADPH Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espectrometría de Masa por Ionización de Electrospray
6.
PLoS One ; 11(7): e0158713, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27410389

RESUMEN

Pear (Pyrus communis) is an economically important fruit crop. Drops in yield and even losses of whole plantations are caused by diseases, most importantly fire blight which is triggered by the bacterial pathogen Erwinia amylovora. In response to the infection, biphenyls and dibenzofurans are formed as phytoalexins, biosynthesis of which is initiated by biphenyl synthase (BIS). Two PcBIS transcripts were cloned from fire blight-infected leaves and the encoded enzymes were characterized regarding substrate specificities and kinetic parameters. Expression of PcBIS1 and PcBIS2 was studied in three pear cultivars after inoculation with E. amylovora. Both PcBIS1 and PcBIS2 were expressed in 'Harrow Sweet', while only PcBIS2 transcripts were detected in 'Alexander Lucas' and 'Conference'. Expression of the PcBIS genes was observed in both leaves and the transition zone of the stem; however, biphenyls and dibenzofurans were only detected in stems. The maximum phytoalexin level (~110 µg/g dry weight) was observed in the transition zone of 'Harrow Sweet', whereas the concentrations were ten times lower in 'Conference' and not even detectable in 'Alexander Lucas'. In 'Harrow Sweet', the accumulation of the maximum phytoalexin level correlated with the halt of migration of the transition zone, whereby the residual part of the shoot survived. In contrast, the transition zones of 'Alexander Lucas' and 'Conference' advanced down to the rootstock, resulting in necrosis of the entire shoots.


Asunto(s)
Erwinia amylovora/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Proteínas de Plantas/genética , Sintasas Poliquetidas/genética , Pyrus/microbiología , Sesquiterpenos/metabolismo , Compuestos de Bifenilo/química , Clonación Molecular , Dibenzofuranos/química , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/metabolismo , Tallos de la Planta/metabolismo , Tallos de la Planta/microbiología , Sintasas Poliquetidas/biosíntesis , Sintasas Poliquetidas/metabolismo , Pyrus/genética , Pyrus/metabolismo , Sesquiterpenos/química , Fitoalexinas
7.
Appl Microbiol Biotechnol ; 99(1): 165-74, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25431013

RESUMEN

The detection of glucoconjugated forms of monoterpene alcohols in rose petals in the late 1960s opened the new field of nonvolatile aroma precursors in flavor research. It is now well established that odorless glycosides represent a significant pool of aroma precursors in plants where they act as preformed but inactivated defense or attractive chemicals. Technical improvements in the separation and identification of plant secondary metabolites have provided a multitude of chemical structures, but functional characterization of glycosyltransferases that catalyze their formation lags behind. As technical efforts and costs for DNA sequencing dramatically dropped during the last decade, the number of plant genome sequences increased significantly, thus providing opportunities to functionally characterize the glycosyltransferase gene families in plants. These studies yielded the first glycosyltransferase genes that encode efficient biocatalysts for the production of monoterpene glucosides. They have applications in the food, feed, chemical, cosmetic, and pharmaceutical industries as slow release aroma chemicals.


Asunto(s)
Cosméticos/metabolismo , Aromatizantes/metabolismo , Glucósidos/metabolismo , Glucosiltransferasas/metabolismo , Monoterpenos/metabolismo , Biotecnología/métodos , Biotecnología/tendencias , Redes y Vías Metabólicas , Plantas/metabolismo , Metabolismo Secundario
8.
Plant Physiol ; 164(4): 2107-22, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24550241

RESUMEN

Proanthocyanidins (PAs) are common polyphenolic polymers of plants found in foliage, fruit, bark, roots, rhizomes, and seed coats that consist of flavan-3-ol units such as 2,3-trans-(+)-catechin and 2,3-cis-(-)-epicatechin. Although the biosynthesis of flavan-3-ols has been studied in angiosperms, little is known about their biosynthesis and ecological roles in gymnosperms. In this study, the genes encoding leucoanthocyanidin reductase, a branch point enzyme involved in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, were identified and functionally characterized in Norway spruce (Picea abies), the most widespread and economically important conifer in Europe. In addition, the accumulation of flavan-3-ols and PAs was investigated in Norway spruce saplings after wounding or inoculation with the fungal pathogen Ceratocystis polonica, which is vectored by bark beetles (Ips typographus) and is usually present during fatal beetle attacks. Monomeric and dimeric flavan-3-ols were analyzed by reverse-phase high-pressure liquid chromatography, while the size and subunit composition of larger PAs were characterized using a novel acid hydrolysis method and normal phase chromatography. Only flavan-3-ol monomers with 2,3-trans stereochemistry were detected in spruce bark; dimeric and larger PAs contained flavan-3-ols with both 2,3-trans and 2,3-cis stereochemistry. Levels of monomers as well as PAs with a higher degree of polymerization increased dramatically in spruce bark after infection by C. polonica. In accordance with their role in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, transcript abundance of Norway spruce LEUCOANTHOCYANIDIN REDUCTASE genes also increased significantly during fungal infection. Bioassays with C. polonica revealed that the levels of 2,3-trans-(+)-catechin and PAs that are produced in the tree in response to fungal infection inhibit C. polonica growth and can therefore be considered chemical defense compounds.


Asunto(s)
Ascomicetos/fisiología , Escarabajos/microbiología , Flavonoides/química , Picea/metabolismo , Picea/microbiología , Corteza de la Planta/parasitología , Animales , Antocianinas/metabolismo , Ascomicetos/crecimiento & desarrollo , Biocatálisis , Vías Biosintéticas/genética , Catequina/metabolismo , Flavonoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Noruega , Filogenia , Picea/enzimología , Picea/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Plantas Modificadas Genéticamente , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Transcripción Genética
9.
PLoS One ; 9(2): e88452, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24551105

RESUMEN

Dendritic cells (DCs) can be sub-divided into various subsets that play specialized roles in priming of adaptive immune responses. Atherosclerosis is regarded as a chronic inflammatory disease of the vessel wall and DCs can be found in non-inflamed and diseased arteries. We here performed a systematic analyses of DCs subsets during atherogenesis. Our data indicate that distinct DC subsets can be localized in the vessel wall. In C57BL/6 and low density lipoprotein receptor-deficient (Ldlr (-/-)) mice, CD11c(+) MHCII(+) DCs could be discriminated into CD103(-) CD11b(+)F4/80(+), CD11b(+)F4/80(-) and CD11b(-)F4/80(-) DCs and CD103(+) CD11b(-)F4/80(-) DCs. Except for CD103(-) CD11b(-) F4/80(-) DCs, these subsets expanded in high fat diet-fed Ldlr (-/-) mice. Signal-regulatory protein (Sirp)-α was detected on aortic macrophages, CD11b(+) DCs, and partially on CD103(-) CD11b(-) F4/80(-) but not on CD103(+) DCs. Notably, in FMS-like tyrosine kinase 3-ligand-deficient (Flt3l (-/-)) mice, a specific loss of CD103(+) DCs but also CD103(-) CD11b(+) F4/80(-) DCs was evidenced. Aortic CD103(+) and CD11b(+) F4/80(-) CD103(-) DCs may thus belong to conventional rather than monocyte-derived DCs, given their dependence on Flt3L-signalling. CD64, postulated to distinguish macrophages from DCs, could not be detected on DC subsets under physiological conditions, but appeared in a fraction of CD103(-) CD11b(+) F4/80(-) and CD11b(+) F4/80(+) cells in atherosclerotic Ldlr (-/-) mice. The emergence of CD64 expression in atherosclerosis may indicate that CD11b(+) F4/80(-) DCs similar to CD11b(+) F4/80(+) DCs are at least in part derived from immigrated monocytes during atherosclerotic lesion formation. Our data advance our knowledge about the presence of distinct DC subsets and their accumulation characteristics in atherosclerosis, and may help to assist in future studies aiming at specific DC-based therapeutic strategies for the treatment of chronic vascular inflammation.


Asunto(s)
Aorta/inmunología , Aorta/patología , Aterosclerosis/inmunología , Aterosclerosis/patología , Células Dendríticas/inmunología , Animales , Antígeno CD11c/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Receptores de IgG/metabolismo , Receptores Inmunológicos/metabolismo
10.
New Phytol ; 201(2): 440-451, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24117941

RESUMEN

Strawberry (Fragaria × ananassa) is a fruit crop with a distinct biphasic flavonoid biosynthesis. Whereas, in the immature receptacle, high levels of proanthocyanidins accumulate, which are associated with herbivore deterrence and pathogen defense, the prominent color-giving anthocyanins are primarily produced in ripe 'fruits' helping to attract herbivores for seed dispersal. Here, constitutive experimental down-regulation of one branch of proanthocyanidin biosynthesis was performed. As a result, the proportion of epicatechin monomeric units within the proanthocyanidin polymer chains was reduced, but this was not the case for the epicatechin starter unit. Shortened chain lengths of proanthocyanidins were also observed. All enzymatic activities for the production of color-giving anthocyanins were already present in unripe fruits at levels allowing a striking red anthocyanin phenotype in unripe fruits of the RNAi silencing lines. An immediately recognizable phenotype was also observed for the stigmata of flowers, which is another epicatechin-forming tissue. Thus, the down-regulation of anthocyanidin reductase (ANR) induced a redirection of the proanthocyanidin pathway, leading to premature and ectopic anthocyanin biosynthesis via enzymatic glycosylation as the alternative pathway. This redirection is also seen in flavonol biosynthesis, which is paralleled by higher pollen viability in silencing lines. ANRi transgenic lines of strawberry provide a versatile tool for the study of the biological functions of proanthocyanidins.


Asunto(s)
Fragaria/metabolismo , Proantocianidinas/biosíntesis , Regulación hacia Abajo , Flavonoides/biosíntesis , Fragaria/genética , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen/genética , Polen/fisiología
11.
Plant Physiol Biochem ; 72: 62-71, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23578977

RESUMEN

Products containing the epiphytic yeast Aureobasidium pullulans are commercially available and applied by fruit growers to prevent several fungal and bacterial diseases of fruit trees. The proposed beneficial mechanisms relate to limitations of space and nutrients for the pathogens in presence of the rapidly proliferating yeast cells. These explanations ignore the potential of yeasts to elicit the plant's defense. Our experiments aim at clarifying if an autoclaved and centrifuged suspension of A. pullulans may induce defense mechanisms. As a model system, the biosynthesis and accumulation of stilbene phytoalexins in callus and shoots of grapevine Vitis vinifera grown in vitro was used. Yeast application to the plant tissue stimulated stilbene biosynthesis, sometimes at the cost of flavonoids. The expression of the gene encoding stilbene synthase was enhanced and the enzyme showed higher activity while chalcone synthase activity and expression was reduced in some cases. An accumulation of stilbenes was also found in transgenic apple trees (Malus domestica cv. Holsteiner Cox) harboring the stilbene synthase-gene under control of its own promoter. These results clearly show that the application of A. pullulans may induce defense mechanisms of the treated plants.


Asunto(s)
Aciltransferasas/metabolismo , Malus/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Sesquiterpenos/metabolismo , Estilbenos/metabolismo , Vitis/metabolismo , Aciltransferasas/genética , Ascomicetos/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Malus/genética , Malus/microbiología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/microbiología , Resveratrol , Vitis/microbiología , Fitoalexinas
12.
Int J Mol Sci ; 13(8): 9992-10009, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22949844

RESUMEN

RNA silencing describes the sequence specific degradation of RNA targets. Silencing is a non-cell autonomous event that is graft transmissible in different plant species. The present study is the first report on systemic acquired dsRNA-mediated gene silencing of transgenic and endogenous gene sequences in a woody plant like apple. Transgenic apple plants overexpressing a hairpin gene construct of the gusA reporter gene were produced. These plants were used as rootstocks and grafted with scions of the gusA overexpressing transgenic apple clone T355. After grafting, we observed a reduction of the gusA gene expression in T355 scions in vitro, but not in T355 scions grown in the greenhouse. Similar results were obtained after silencing of the endogenous Mdans gene in apple that is responsible for anthocyanin biosynthesis. Subsequently, we performed grafting experiments with Mdans silenced rootstocks and red leaf scions of TNR31-35 in order to evaluate graft transmitted silencing of the endogenous Mdans. The results obtained suggested a graft transmission of silencing signals in in vitro shoots. In contrast, no graft transmission of dsRNA-mediated gene silencing signals was detectable in greenhouse-grown plants and in plants grown in an insect protection tent.


Asunto(s)
Silenciador del Gen , Malus/inmunología , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Raíces de Plantas/inmunología , Plantas Modificadas Genéticamente/inmunología , ARN Interferente Pequeño/genética , Agrobacterium tumefaciens/fisiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Malus/genética , Malus/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/microbiología , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Opt Express ; 20 Suppl 2: A205-12, 2012 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-22418669

RESUMEN

The efficiency of organic light-emitting diodes (OLEDs) is still limited by poor light outcoupling. In particular, the excitation of surface plasmon polaritons (SPPs) at metal-organic interfaces represents a major loss channel. By combining optical simulations and experiments on simplified luminescent thin-film structures we elaborate the conditions for the extraction of SPPs via coupling to high-index media. As a proof-of-concept, we demonstrate the possibility to extract light from wave-guided modes and surface plasmons in a top-emitting white OLED by a high-index prism.

14.
Plant Physiol Biochem ; 51: 18-25, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22153235

RESUMEN

Transgenic antisense flavanone-3-hydroxylase apple plants were produced to mimic the effect of the agrochemical prohexadione-Ca on apple leaves. This enzyme inhibitor for 2-oxoglutarate dependent dioxygenases is used as a growth retardant and for control of secondary fire blight of leaves. Like using the agent, silencing of flavanone-3-hydroxylase leads to an accumulation of flavanones in leaves, but in contrast not to the formation of 3-deoxyflavonoids. In prohexadione-Ca treated leaves the 3-deoxyflavonoid luteoforol is formed from accumulating flavanones, acting as an antimicrobial compound against the fire blight pathogen Erwinia amylovora. Seemingly, the silencing of just one of the 2-oxoglutarate dependent dioxygenases (in apple also flavonol synthase and anthocyanidin synthase take part downstream in the pathway) does not provide a sufficiently high ratio of flavanones to dihydroflavonols. This seems to be needed to let the dihydroflavonol-4-reductase/flavanone-4-reductase enzyme reduce flavanones to luteoforol, and to let this be reduced by the leucoanthocyanidin-4-reductase/3-deoxyleucoanthocyanidin-4-reductase, each acting with their respective weak secondary activities. Accordingly, also the intended inducible resistance to fire blight by prohexadione-Ca is not observed with the antisense flavanone-3-hydroxylase apple plants. On the other hand, for most transgenic lines with strong flavanone-4-reductase down-regulation, up-regulation of gene expression for the other flavonoid genes was found. This provides further evidence for the feedback regulation of flavonoid gene expression having been previously reported for the prohexadione-Ca inhibited apple plants.


Asunto(s)
Flavanonas/biosíntesis , Silenciador del Gen , Malus/genética , Oxigenasas de Función Mixta/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Antibacterianos/metabolismo , Antibacterianos/farmacología , Benzopiranos/metabolismo , Benzopiranos/farmacología , Clonación Molecular , Medios de Cultivo/metabolismo , Susceptibilidad a Enfermedades/inmunología , Susceptibilidad a Enfermedades/microbiología , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Erwinia amylovora/efectos de los fármacos , Erwinia amylovora/inmunología , Erwinia amylovora/patogenicidad , Flavanonas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Ácidos Cetoglutáricos/farmacología , Malus/enzimología , Malus/inmunología , Malus/microbiología , Oxigenasas de Función Mixta/genética , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacología , Brotes de la Planta/enzimología , Brotes de la Planta/microbiología , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/inmunología , Plantas Modificadas Genéticamente/microbiología , Plásmidos/genética , Plásmidos/metabolismo , Transcripción Genética
15.
Clin Appl Thromb Hemost ; 17(6): 605-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21593023

RESUMEN

It has been speculated that the atypical clinical presentation of acute pulmonary embolism (PE) in older patients leads to a late diagnosis and therefore contributes to a worse prognosis. Therefore, we prospectively evaluated the delay in diagnosis and its relation to the in-hospital mortality in 202 patients with acute PE. Patients >65 years presented more often with hypoxia (P = .017) and with a history of syncope (P = .046). Delay in diagnosis was not statistically different in both age groups. Older age was significantly associated with an increased risk for in-hospital mortality (OR 4.36, 95% CI 0.93-20.37, P = .043), whereas the delay in diagnosis was not associated with an increase of in-hospital mortality. We therefore conclude that the clinical presentation of acute PE in older patients cannot be considered as a risk factor for late diagnosis and is not responsible for their higher in-hospital death rate.


Asunto(s)
Embolia Pulmonar/diagnóstico , Enfermedad Aguda , Factores de Edad , Anciano , Anciano de 80 o más Años , Diagnóstico Tardío , Femenino , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Factores de Riesgo
16.
BMC Evol Biol ; 10: 337, 2010 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-21044353

RESUMEN

BACKGROUND: Structural elucidation and analysis of fructifications of plants is fundamental for understanding their evolution. In case of Ginkgo biloba, attention was drawn by Fujii in 1896 to aberrant fructifications of Ginkgo biloba whose seeds are attached to leaves, called O-ha-tsuki in Japan. This well-known phenomenon was now interpreted by Fujii as being homologous to ancestral sporophylls. The common fructification of Ginkgo biloba consists of 1-2 (rarely more) ovules on a dichotomously divided stalk, the ovules on top of short stalklets, with collars supporting the ovules. There is essentially no disagreement that either the whole stalk with its stalklets, collars and ovules is homologous to a sporophyll, or, alternatively, just one stalklet, collar and ovule each correspond to a sporophyll. For the transition of an ancestral sporophyll resembling extant O-ha-tsuki aberrant leaves into the common fructification with stalklet/collar/ovule, evolutionary reduction of the leaf lamina of such ancestral sporophylls has to be assumed. Furthermore, such ancestral sporophylls would be expected in the fossil record of ginkgophytes. RESULTS: From the Upper Permian of the Bletterbach gorge (Dolomites, South Tyrol, Italy) ginkgophyte leaves of the genus Sphenobaiera were discovered. Among several specimens, one shows putatively attached seeds, while other specimens, depending on their state of preservation, show seeds in positions strongly suggesting such attachment. Morphology and results of a cuticular analysis are in agreement with an affiliation of the fossil to the ginkgophytes and the cuticle of the seed is comparable to that of Triassic and Jurassic ones and to those of extant Ginkgo biloba. The Sphenobaiera leaves with putatively attached seeds closely resemble seed-bearing O-ha-tsuki leaves of extant Ginkgo biloba. This leads to the hypothesis that, at least for some groups of ginkgophytes represented by extant Ginkgo biloba, such sporophylls represent the ancestral state of fructifications. CONCLUSIONS: Some evidence is provided for the existence of ancestral laminar ginkgophyte sporophylls. Homology of the newly found fossil ginkgophyte fructifications with the aberrant O-ha-tsuki fructifications of Ginkgo biloba is proposed. This would support the interpretation of the apical part of the common Ginkgo biloba fructification (stalklet/collar/ovule) as a sporophyll with reduced leaf lamina.


Asunto(s)
Fósiles , Ginkgo biloba , Italia , Filogenia , Hojas de la Planta
17.
Adv Ther ; 27(9): 648-54, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20694805

RESUMEN

INTRODUCTION: The effects of thrombolysis on the clinical outcome of patients with intermediate-risk pulmonary embolism (PE) are still under debate. The effect of thrombolysis on the length of stay (LOS) in hospital is unknown. The aim of this study was to identify factors associated with LOS and to investigate whether LOS is suitable to assess effectiveness of thrombolysis in patients with intermediate-risk PE. METHODS: Data were reviewed from December 2005 until October 2009. The LOS in the intensive care unit (ICU) was expressed in hours, and total LOS was recorded in days. Total LOS was not noted in case of preterm withdrawal of therapy or death. RESULTS: Of a total of 202 patients, 84 received alteplase plus heparin and 118 patients were treated with anticoagulants alone. Total median LOS was significantly shorter (10 vs. 12 days) in the alteplase group (P=0.005), while there was no difference in the LOS in the ICU. Age above 65 years (P=0.036) and comorbidity (P<0.001) were independent predictors for a prolonged hospital stay, whereas thrombolysis independently predicted a shorter total LOS in multivariate analysis (P=0.001). Thrombolysis has shown to be able to independently predict home discharge (P=0.029). CONCLUSION: LOS is influenced by patient-related factors such as age and comorbidity. Thrombolysis may lead to a reduction of total median LOS for patients with intermediate-risk PE, possibly indicating that it is more effective than anticoagulant therapy alone in this group of patients.


Asunto(s)
Fibrinolíticos , Tiempo de Internación , Administración del Tratamiento Farmacológico , Embolia Pulmonar/prevención & control , Terapia Trombolítica/efectos adversos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Comorbilidad , Contraindicaciones , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/efectos adversos , Insuficiencia Cardíaca/epidemiología , Hemorragia/inducido químicamente , Heparina/administración & dosificación , Heparina/efectos adversos , Humanos , Unidades de Cuidados Intensivos , Enfermedades Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Embolia Pulmonar/sangre , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/epidemiología , Embolia Pulmonar/fisiopatología , Radiografía , Medición de Riesgo , Terapia Trombolítica/mortalidad , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/efectos adversos , Resultado del Tratamiento
18.
Planta ; 231(3): 623-35, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19967387

RESUMEN

Transgenic apple plants (Malus x domestica cv. 'Holsteiner Cox') overexpressing the Leaf Colour (Lc) gene from maize (Zea mays) exhibit strongly increased production of anthocyanins and flavan-3-ols (catechins, proanthocyanidins). Greenhouse plants investigated in this study exhibit altered phenotypes with regard to growth habit and resistance traits. Lc-transgenic plants show reduced size, transversal gravitropism of lateral shoots, reduced trichome development, and frequently reduced shoot diameter and abnormal leaf development with fused leaves. Such phenotypes seem to be in accordance with a direct or an indirect effect on polar-auxin-transport in the transgenic plants. Furthermore, leaves often develop necrotic lesions resembling hypersensitive response lesions. In tests, higher resistance against fire blight (caused by the bacterium Erwinia amylovora) and against scab (caused by the fungus Venturia inaequalis) is observed. These phenotypes are discussed with respect to the underlying altered physiology of the Lc-transgenic plants. The results are expected to be considered in apple breeding strategies.


Asunto(s)
Malus/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Factores de Transcripción/genética , Ascomicetos , Erwinia amylovora , Inmunidad Innata/genética , Malus/crecimiento & desarrollo , Malus/microbiología , Fenotipo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/anatomía & histología , Plantas Modificadas Genéticamente/microbiología , Ploidias , Factores de Transcripción/metabolismo , Transcripción Genética , Zea mays/genética
19.
J Agric Food Chem ; 57(9): 3512-8, 2009 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-19338353

RESUMEN

The inability of most European grapevines ( Vitis vinifera ) to produce 3,5-di-O-glucosides of anthocyanidin-3-O-glucosides while in other Vitis species diglucosides are found has long been used as a diagnostic tool for the classification of wines according to their varietal origin. A functional 5-O-glucosyltransferase (5GT) gene and its nonfunctional allele were recently cloned from the heterozygous hybrid cultivar 'Regent'. Protein sequence comparison revealed only five amino acid substitutions and a truncation at the C-terminus in the inactive enzyme. Restoration of the C-terminus in the European allele alone proved to be insufficient for a reversal to a functional allele. An additional V121L transition located in close spatial vicinity of the catalytically active histidine in the active site of the nonfunctional protein was also essential to recover 5GT activity. Thus, two mutations render the 5GT inactive in V. vinifera and explain why revertants for this mutant allele have not been observed in breeding programs. The results have a significant effect on the classification and breeding of Vitis varieties and the evaluation of derived products.


Asunto(s)
Aciltransferasas/genética , Aciltransferasas/metabolismo , Mutación/genética , Vitis/enzimología , Aciltransferasas/química , Alelos , Secuencia de Aminoácidos , Cruzamiento , Dominio Catalítico , Expresión Génica , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Vitis/clasificación
20.
Planta ; 229(3): 681-92, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19066943

RESUMEN

We have investigated the consequences of blocking anthocyanin biosynthesis by silencing a key enzyme, anthocyanidin synthase, in transgenic plants of a red-leaved apple cultivar. This is complementary to a previous study of induction of anthocyanin biosynthesis by overexpressing a heterologous transcription factor. Analysis of these opposite phenotypes allows one to study anthocyanin functions in apple and to test the influence of the genetic manipulation on other, related metabolites. As expected, anthocyanin biosynthesis was almost completely blocked and this was accompanied by a shift in the profile of flavonoids and related polyphenols. Most interestingly, a rise in epicatechin was found. A severe reduction of viability by necrotic leaf lesions was also observed, suggesting an essential function of anthocyanins in apple.


Asunto(s)
Flavonoides/biosíntesis , Malus/genética , Oxigenasas/genética , Proteínas de Plantas/genética , Antocianinas/biosíntesis , Antocianinas/fisiología , Catequina/metabolismo , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Malus/anatomía & histología , Malus/metabolismo , Fenoles , Fenotipo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Polifenoles , ARN Mensajero/metabolismo
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