Structural synaptic elements are differentially regulated in superior temporal cortex of schizophrenia patients

Inaccurate wiring and synaptic pathology appear to be major hallmarks of schizophrenia. A variety of gene products involved in synaptic neurotransmission and receptor signaling are differentially expressed in brains of schizophrenia patients. However, synaptic pathology may also develop by improper expression of intra- and extra-cellular structural elements weakening synaptic stability. Therefore, we have investigated transcription of these elements in the left superior temporal gyrus of 10 schizophrenia patients and 10 healthy controls by genome-wide microarrays (Illumina). Fourteen up-regulated and 22 downregulated genes encoding structural elements were chosen from the lists of differentially regulated genes for further qRT-PCR analysis. Almost all genes confirmed by this method were downregulated. Their gene products belonged to vesicle-associated proteins, that is, synaptotagmin 6 and syntaxin 12, to cytoskeletal proteins, like myosin 6, pleckstrin, or to proteins of the extracellular matrix, such as collagens, or laminin C3. Our results underline the pivotal roles of structural genes that control formation and stabilization of pre- and post-synaptic elements or influence axon guidance in schizophrenia. The glial origin of collagen or laminin highlights the close interrelationship between neurons and glial cells in establishment and maintenance of synaptic strength and plasticity. It is hypothesized that abnormal expression of these and related genes has a major impact on the pathophysiology of schizophrenia.

Space-time relation of post-collisional granitic magmatism in Santa Catarina, southern Brazil: U-Pb LA-MC-ICP-MS zircon geochronology of coeval mafic-felsic magmatism related to the Major Gercino Shear Zone

LA-MC-ICP-MS U-Pb zircon dating was performed on syntectonic, early post-collisional granitic and associated mafic rocks that are intrusive in the Brusque Metamorphic Complex and in the Florianopolis Batholith, major tectonic domains separated by the Neoproterozoic Major Gercino Shear Zone (MGSZ) in south Brazil. The inferred ages of magmatic crystallization are consistent with field relationships, and show that the syntectonic granites from both domains are similar, with ages around 630-620 Ma for high-K calc-alkaline metaluminous granites and ca. 610 Ma for slightly peraluminous granites. Although ca. 650 Ma inherited zircon components are identified in granites from both domains, important contrasts on the crustal architecture in each domain are revealed by the patterns of zircon inheritance, indicating different crustal sources for the granites in each domain. The granites from the southern domain (Floriandpolis Batholith) have essentially Neoproterozoic (650-700 Ma and 900-950 Ma) inheritance; with a single 2.0-2.2 Ga inherited age obtained in the peraluminous Mariscal Granite. In the northern Brusque Metamorphic Complex, the metaluminous Rio Pequeno Granite and associated mafic rocks have scarce inherited cores with ages around 1.65 Ga, whereas the slightly peraluminous Serra dos Macacos Granite has abundant Paleoproterozoic (1.8-2.2 Ga) and Archean (2.9-3.4 Ga) inherited zircons. Our results are consistent with the hypothesis that the MGSZ separates domains with distinct geologic evolution; however, the contemporaneity of 630-610 Ma granitic magmatism with similar structural and geochemical patterns on both sides of this major shear zone indicates that these domains were already part of a single continental mass at 630 Ma, reinforcing the post-collisional character of these granites. (C) 2012 Elsevier B.V. All rights reserved.

A comparison for a multiscale study of structural lineaments in southern Brazil: LANDSAT-7 ETM+ and shaded relief images from SRTM3-DEM

This paper presents a comparison of descriptive statistics obtained for brittle structural lineaments extracted manually from LANDSAT images and shaded relief images from SRTM 3 DEM at 1:100, 000 and 1:500, 000 scales. The selected area is located in the southern of Brazil and comprises Precambrian rocks and stratigraphic units of the Paraná Basin. The application of this methodology shows that the visual interpretation depends on the kind of remote sensing image. The resulting descriptive statistics obtained for lineaments extracted from the images do not follow the same pattern according to the scale adopted. The main direction obtained for Proterozoic rocks using both image types at a 1:500, 000 scale are close to NS±10, whereas at a 1:100, 000 scale N45E was obtained for shaded relief images from SRTM 3 DEM and N10W for LANDSAT images. The Paleozoic sediments yielded the best results for the different images and scales (N50W). On the other hand, the Mesozoic igneous rocks showed greatest differences, the shaded relief images from SRTM 3 DEM images highlighting NE structures and the LANDSAT images highlighting NW structures. The accumulated frequency demonstrated high similarity between products for each image type no matter the scale, indicating that they can be used in multiscale studies. Conversely, major differences were found when comparing data obtained using shaded relief images from SRTM 3 DEM and Landsat images at a 1:100, 000 scale.

Morphogenetic and structural characteristics of guinea grass tillers at different ages under intermittent stocking

The objective of this research was to assess morphogenetic and structural characteristics of tillers of guinea grass cv. Tanzania at different ages. The pastures of guinea grass were managed in six pasture conditions related to the combination of three frequencies (90, 95, and 99% light interception) and two post-grazing heights (25 and 50 cm). In these six pastures conditions, three tiller ages were evaluated (young, mature, and old). The design was of completely randomized block with three replications. Young tillers exhibited higher leaf appearance rate and leaf elongation rate and, consequently, higher final leaf length and number of live leaves than mature and old tillers, regardless of the pasture condition. On pastures managed with 90 or 95% light interception associated with a post-grazing height of 25 cm, old tillers presented longer leaf lifespan than young and mature ones. There is a progressive reduction in the vigor of growth of pastures of guinea grass cv. Tanzania with advancing tiller age.

Cell therapy prevents structural, functional and molecular remodeling of remote non-infarcted myocardium

Background/objectives: Therapy using bone marrow (BM) cells has been tested experimentally and clinically due to the potential ability to restore cardiac function by regenerating lost myocytes or increasing the survival of tissues at risk after myocardial infarction (MI). In this study we aimed to evaluate whether BM-derived mononuclear cell (MNC) implantation can positively influence the post-MI structural remodeling, contractility and Ca(2 +)-handling proteins of the remote non-infarcted tissue in rats. Methods and results: After 48 h of MI induction, saline or BM-MNC were injected. Six weeks later, MI scars were slightly smaller and thicker, and cardiac dilatation was just partially prevented by cell therapy. However, the cardiac performance under hemodynamic stress was totally preserved in the BM-MNC treated group if compared to the untreated group, associated with normal contractility of remote myocardium as analyzed in vitro. The impaired post-rest potentiation of contractile force, associated with decreased protein expression of the sarcoplasmic reticulum Ca2 +-ATPase and phosphorylated-phospholamban and overexpression of Na(+)/Ca(2 +) exchanger, were prevented by BM-MNC, indicating preservation of the Ca(2 +) handling. Finally, pathological changes on remodeled remote tissue such as myocyte hypertrophy, interstitial fibrosis and capillary rarefaction were also mitigated by cell therapy. Conclusions: BM-MNC therapy was able to prevent cardiac structural and molecular remodeling after MI, avoiding pathological changes on Ca(2 +)-handling proteins and preserving contractile behavior of the viable myocardium, which could be the major contributor to the improvements of global cardiac performance after cell transplantation despite that scar tissue still exists.

Theoretical and experimental studies on the electronic, optical, and structural properties of poly-pyrrole-2-carboxylic acid films

A theoretical approach is used here to explain experimental results obtained from the electrosynthesis of polypyrrole-2-carboxylic acid (PPY-2-COOH) films in nonaqueous medium. An analysis of the Fukui function (reactivity index) indicates that the monomer (pyrrole-2-carboxylic acid, PY-2-COOH), and dimers and trimers are oxidized in the C4 or C5 positions of the heterocyclic ring of the PY-2-COOH structure. After calculating the heat of formation using semiempirical Austin Model 1 post-Hartree-Fock parameterization for dimer species, both C4 and C5 positions adjacent to the aromatic rings of PPY-2-COOH were considered the most susceptible ones to oxidative coupling reactions. The ZINDO-S/CI semiempirical method was used to simulate the electronic transitions typically seen in the UV-VIS-NIR range in monomer and oligomers with different conjugation lengths. The use of an electrochemical quartz crystal microbalance provides sufficient information to propose a polymerization mechanism of PY-2-COOH based on molecular modeling and experimental results.