Absorção, translocação e utilização de zinco, cobre e manganês por mudas enxertadas de Coffea arabica

Comparativamente ao pé-franco, a combinação enxerto/porta-enxerto altera os complexos mecanismos de "feedback" entre parte aérea e raízes, afetando de maneira positiva ou negativa a eficiência nutricional da planta. Este trabalho teve como objetivo avaliar, em cultivo hidropônico, a eficiência da absorção, translocação e utilização de Zn, Cu e Mn por mudas de Coffea arabica L., de acordo com o porta-enxerto utilizado. O experimento foi realizado em casa de vegetação, por um período de 170 dias, em vasos que continham areia como substrato, recebendo solução nutritiva circulante. Utilizaram-se, como enxerto, quatro genótipos de C. arabica: os cultivares Catuaí Vermelho IAC 15 e Oeiras MG 6851 e os híbridos 'H 419-10-3-1-5' e 'H 514-5-5-3' , e, como porta-enxerto, quatro genótipos, sendo três de Coffea canephora Pierre ex Froenher: Apoatã LC 2258, Conilon Muriaé-1 e RC EMCAPA 8141 (recombinação entre clones da variedade Robustão Capixaba - EMCAPA 8141) e uma linhagem de Coffea arabica L.: Mundo Novo IAC 376-4, além de quatro pés-francos. O delineamento experimental utilizado foi em blocos casualizados com 20 tratamentos, quatro repetições e uma planta por parcela. A eficiência nutricional das mudas quanto ao Zn, Cu e Mn variou de acordo com a combinação enxerto/porta-enxerto. A progênie 'H 514-5-5-3' foi mais eficiente quanto à utilização de Zn, Cu e Mn e produção de matéria seca, quando combinada com os porta-enxertos Apoatã LC 2258 e Mundo Novo IAC 376-4. O Catuaí Vermelho IAC 15 foi mais eficiente na utilização de Cu e Mn quando combinado com Apoatã LC 2258.

Mental disorders in offspring of parents with bipolar and major depressive disorders.

OBJECTIVES: There is limited information on the specificity of associations between parental bipolar disorder (BPD) and major depressive disorder (MDD) and the risk of psychopathology in offspring. The chief aim of the present study was to investigate the association between mood disorder subtypes in the two parents and mental disorders in the offspring. METHODS: A total of 376 offspring (aged 6.0-17.9 years; mean=11.5years) of 72 patients with BPD (139 offspring), 56 patients with MDD (110 offspring), and 66 controls (127 offspring) participated in a family study conducted in two university hospital centers in Switzerland. Probands, offspring, and biological co-parents were interviewed by psychologists blind to proband diagnoses, using a semi-structured diagnostic interview. RESULTS: Rates of mood and anxiety disorders were elevated among offspring of BPD probands (34.5% any mood; 42.5% any anxiety) and MDD probands (25.5% any mood; 44.6% any anxiety) as compared to those of controls (12.6% any mood; 22.8% any anxiety). Moreover, recurrent MDD was more frequent among offspring of BPD probands (7.9%) than those of controls (1.6%). Parental concordance for bipolar spectrum disorders was associated with a further elevation in the rates of mood disorders in offspring (64.3% both parents versus 27.2% one parent). CONCLUSIONS:   These findings provide unique information on the broad manifestations of parental mood disorders in their offspring. The earlier onset and increased risk of recurrent MDD in the offspring of parents with BPD compared to those of controls suggests that the episodicity characterizing BPD may emerge in childhood and adolescence.

Mineralogical, K-Ar, stable and Sr isotope systematics of K-white micas during very low-grade metamorphism of limestones (Helvetic nappes, Western Switzerland)

Mineralogical, K-Ar, Rb-Sr and stable isotope analyses have been carried out on K-white micas from Helvetic Malm limestones in order to examine their evolution during very low- to low-grade Alpine metamorphism, associated with intense ductile deformation. Metamorphic temperatures were estimated al approximately 300-degrees-C from stable isotopes (quartz-calcite thermometry), occurrence of chloritoid, and `'epizonal'' illite crystallinity index. K-white micas consist of variable mixtures of 2M, phengite and muscovite, as revealed by detailed X-ray diffraction analyses using peak decomposition of the (060, 331) spectra. K-Ar apparent ages display a strong grain-size dependence in which mainly fine-grained size fractions (< 2 mum) record Alpine ages (37-15 Ma). However, these ages provide a relative rather than an absolute chronology of the diachronous Alpine metamorphic evolution of the Helvetic nappes. The resetting of the K-Ar isotopic system of K-white micas to Alpine metamorphic conditions reflects an apparent combination of crystallization/recrystallization and radiogenic Ar-40 diffusion loss. The oxygen isotope compositions of micas (+ 15 to + 22 parts per thousand) are intermediate between detrital and O-18-enriched values expected for micas neoformed within an abundant marine carbonate matrix. No isotopic equilibrium has been reached between calcite and micas. The variable depletion of hydrogen isotope compositions (- 126 to - 82 parts per thousand) is influenced by the interaction with organic matter under closed-system conditions. Organic matter, if not removed, may also represent a serious source of error in K-Ar age determination, by introducing radiogenic Ar-40 contamination. Sr-87/Sr-86 isotope ratios of micas range from 0.70879 to 0.70902 with one outlier at 0.71794. The low values reflect Sr exchange with calcite occurring during crystallization/recrystallization of micas under closed-system conditions.

Diffusion tensor imaging shows structural remodeling of stroke mirror region: results from a pilot study.

Background: The role of the non-injured hemisphere in stroke recovery is poorly understood. In this pilot study, we sought to explore the presence of structural changes detectable by diffusion tensor imaging (DTI) in the contralesional hemispheres of patients who recovered well from ischemic stroke. Methods: We analyzed serial DTI data from 16 stroke patients who had moderate initial neurological deficits (NIHSS scores 3-12) and good functional outcome at 3-6 months (NIHSS score 0 or modified Rankin Score ≤1). We segmented the brain tissue in gray and white matter (GM and WM) and measured the apparent diffusion coefficient (ADC) and fractional anisotropy in the infarct, in the contralesional infarct mirror region as well as in concentrically expanding regions around them. Results: We found that GM and WM ADC significantly increased in the infarct region (p < 0.01) from acute to chronic time points, whereas in the infarct mirror region, GM and WM ADC increased (p < 0.01) and WM fractional anisotropy decreased (p < 0.05). No significant changes were detected in other regions. Conclusion: DTI-based metrics are sensitive to regional structural changes in the contralesional hemisphere during stroke recovery. Prospective studies in larger cohorts with varying levels of recovery are needed to confirm our findings.

A regulatory network for the efficient control of transgene expression.

BACKGROUND: Expression of heterologous genes in mammalian cells or organisms for therapeutic or experimental purposes often requires tight control of transgene expression. Specifically, the following criteria should be met: no background gene activity in the off-state, high gene expression in the on-state, regulated expression over an extended period, and multiple switching between on- and off-states. METHODS: Here, we describe a genetic switch system for controlled transgene transcription using chimeric repressor and activator proteins functioning in a novel regulatory network. In the off-state, the target transgene is actively silenced by a chimeric protein consisting of multimerized eukaryotic transcriptional repression domains fused to the DNA-binding tetracycline repressor. In the on-state, the inducer drug doxycycline affects both the derepression of the target gene promoter and activation by the GAL4-VP16 transactivator, which in turn is under the control of an autoregulatory feedback loop. RESULTS: The hallmark of this new system is the efficient transgene silencing in the off-state, as demonstrated by the tightly controlled expression of the highly cytotoxic diphtheria toxin A gene. Addition of the inducer drug allows robust activation of transgene expression. In stably transfected cells, this control is still observed after months of repeated cycling between the repressed and activated states of the target genes. CONCLUSIONS: This system permits tight long-term regulation when stably introduced into cell lines. The underlying principles of this network system should have general applications in biotechnology and gene therapy.

Landscape structure affects dispersal in the greater white-toothed shrew: inference between genetic and simulated ecological distances

Animal dispersal in a fragmented landscape depends on the complex interaction between landscape structure and animal behavior. To better understand how individuals disperse, it is important to explicitly represent the properties of organisms and the landscape in which they move. A common approach to modelling dispersal includes representing the landscape as a grid of equal sized cells and then simulating individual movement as a correlated random walk. This approach uses a priori scale of resolution, which limits the representation of all landscape features and how different dispersal abilities are modelled. We develop a vector-based landscape model coupled with an object-oriented model for animal dispersal. In this spatially explicit dispersal model, landscape features are defined based on their geographic and thematic properties and dispersal is modelled through consideration of an organism's behavior, movement rules and searching strategies (such as visual cues). We present the model's underlying concepts, its ability to adequately represent landscape features and provide simulation of dispersal according to different dispersal abilities. We demonstrate the potential of the model by simulating two virtual species in a real Swiss landscape. This illustrates the model's ability to simulate complex dispersal processes and provides information about dispersal such as colonization probability and spatial distribution of the organism's path

Toward synthetic combinatorial peptide libraries in positional scanning format (PS-SCL)-based identification of CD8+ Tumor-reactive T-Cell Ligands: a comparative analysis of PS-SCL recognition by a single tumor-reactive CD8+ cytolytic T-lymphocyte clone.

The use of synthetic combinatorial peptide libraries in positional scanning format (PS-SCL) has emerged recently as an alternative approach for the identification of peptides recognized by T lymphocytes. The choice of both the PS-SCL used for screening experiments and the method used for data analysis are crucial for implementing this approach. With this aim, we tested the recognition of different PS-SCL by a tyrosinase 368-376-specific CTL clone and analyzed the data obtained with a recently developed biometric data analysis based on a model of independent and additive contribution of individual amino acids to peptide antigen recognition. Mixtures defined with amino acids present at the corresponding positions in the native sequence were among the most active for all of the libraries. Somewhat surprisingly, a higher number of native amino acids were identifiable by using amidated COOH-terminal rather than free COOH-terminal PS-SCL. Also, our data clearly indicate that when using PS-SCL longer than optimal, frame shifts occur frequently and should be taken into account. Biometric analysis of the data obtained with the amidated COOH-terminal nonapeptide library allowed the identification of the native ligand as the sequence with the highest score in a public human protein database. However, the adequacy of the PS-SCL data for the identification for the peptide ligand varied depending on the PS-SCL used. Altogether these results provide insight into the potential of PS-SCL for the identification of CTL-defined tumor-derived antigenic sequences and may significantly implement our ability to interpret the results of these analyses.

Intussusception like lesion after fenestration in aortic type B dissection.

We report on a patient with Marfan syndrome who presented a Stanford type B dissection of the descending thoracic aorta in late pregnancy. After a cesarean section, the patient presented a severe obstruction of the mesenteric superior artery. An endovascular fenestration was performed (balloon and guidewire based fenestration). Computed tomography (CT) angiography revealed an intussusception 'like' image of the abdominal aortic layers as a consequence of the fenestration procedure. Because of aneurismal progression in the abdominal aorta, surgical repair of the abdominal aorta and intussusception material removal was achieved six weeks later. The patient is currently in good condition. We conclude that the intussusception could be induced by a guidewire. This fenestration procedure is not recommended in patients with structural aortic disorders.

O-GlcNAc transferase catalyzes site-specific proteolysis of HCF-1.

The human epigenetic cell-cycle regulator HCF-1 undergoes an unusual proteolytic maturation process resulting in stably associated HCF-1(N) and HCF-1(C) subunits that regulate different aspects of the cell cycle. Proteolysis occurs at six centrally located HCF-1(PRO)-repeat sequences and is important for activation of HCF-1(C)-subunit functions in M phase progression. We show here that the HCF-1(PRO) repeat is recognized by O-linked β-N-acetylglucosamine transferase (OGT), which both O-GlcNAcylates the HCF-1(N) subunit and directly cleaves the HCF-1(PRO) repeat. Replacement of the HCF-1(PRO) repeats by a heterologous proteolytic cleavage signal promotes HCF-1 proteolysis but fails to activate HCF-1(C)-subunit M phase functions. These results reveal an unexpected role of OGT in HCF-1 proteolytic maturation and an unforeseen nexus between OGT-directed O-GlcNAcylation and proteolytic maturation in HCF-1 cell-cycle regulation.

[Voyage en Italie : 1824-1830]. , Peintures dans la chambre des prêtres du Temple de Vénus : [décor mural et tableau central représentant Dionysos, Silène et la panthère] : [dessin] / h. L. [Henri Labrouste]

Référence bibliographique : Weigert, 376