Dynamic Changes in the Mental Rotation Network Revealed by Pattern Recognition Analysis of fMRI Data

We investigated the temporal dynamics and changes in connectivity in the mental rotation network through the application of spatio-temporal support vector machines (SVMs). The spatio-temporal SVM [Mourao-Miranda, J., Friston, K. J., et al. (2007). Dynamic discrimination analysis: A spatial-temporal SVM. Neuroimage, 36, 88-99] is a pattern recognition approach that is suitable for investigating dynamic changes in the brain network during a complex mental task. It does not require a model describing each component of the task and the precise shape of the BOLD impulse response. By defining a time window including a cognitive event, one can use spatio-temporal fMRI observations from two cognitive states to train the SVM. During the training, the SVM finds the discriminating pattern between the two states and produces a discriminating weight vector encompassing both voxels and time (i.e., spatio-temporal maps). We showed that by applying spatio-temporal SVM to an event-related mental rotation experiment, it is possible to discriminate between different degrees of angular disparity (0 degrees vs. 20 degrees, 0 degrees vs. 60 degrees, and 0 degrees vs. 100 degrees), and the discrimination accuracy is correlated with the difference in angular disparity between the conditions. For the comparison with highest accuracy (08 vs. 1008), we evaluated how the most discriminating areas (visual regions, parietal regions, supplementary, and premotor areas) change their behavior over time. The frontal premotor regions became highly discriminating earlier than the superior parietal cortex. There seems to be a parcellation of the parietal regions with an earlier discrimination of the inferior parietal lobe in the mental rotation in relation to the superior parietal. The SVM also identified a network of regions that had a decrease in BOLD responses during the 100 degrees condition in relation to the 0 degrees condition (posterior cingulate, frontal, and superior temporal gyrus). This network was also highly discriminating between the two conditions. In addition, we investigated changes in functional connectivity between the most discriminating areas identified by the spatio-temporal SVM. We observed an increase in functional connectivity between almost all areas activated during the 100 degrees condition (bilateral inferior and superior parietal lobe, bilateral premotor area, and SMA) but not between the areas that showed a decrease in BOLD response during the 100 degrees condition.

Influence of neodymium ions on photocatalytic activity of TiO(2) synthesized by sol-gel and precipitation methods

Titanium dioxide with and without the addition of neodymium ions was prepared using sol-gel and precipitation methods. The resulting catalysts were characterized by thermal analysis, X-ray diffraction and BET specific surface area. Neodymium addition exerted a remarkable influence on the phase transition temperature and the surface properties of the TiO(2) matrix. TiO(2) samples synthesized by precipitation exhibit an exothermic event related from the amorphous to anatase phase transition at 510 degrees C, whereas in Nd-doped TiO(2) this transition occurred at 527 degrees C. A similar effect was observed in samples obtained using sol-gel method. The photocatalytic reactivity of the catalysts was evaluated by photodegradation of Remazol Black B (RB) under ultraviolet irradiation. Nd-doped TiO(2) showed enhanced photodegradation ability compared to undoped TiO(2) samples, independent of the method of synthesis. In samples obtained by sol-gel, RB decoloration was enhanced by 16% for TiO(2) doped with 0.5% neodymium ions. (C) 2010 Elsevier B.V. All rights reserved.

Synthesis and characterization of trans-[Ru(NO)Cl(L)(4)](PF(6))(2) (L = isonicotinamide; 4-acetylpyridine) and related species

The trans-[RUCl(2)(L)(4)], trans-[Ru(NO)Cl (L)(4)](PF(6))(2) (L = isonicotinamide and 4-acetylpyridine) and trans-[Ru(NO)(OH)(py)(4)]Cl(2) (py = pyridine) complexes have been prepared and characterized by elemental analysis, UV-visible, infrared, and (1)H NMR spectroscopies, and cyclic voltammetry. The MLCT band energies of trans-[RUCl(2)(L)(4) increase in the order 4-acpy < isn < py. The reduction potentials of trans-[RuCl(2)(L)(4)] and trans-[Ru(NO)Cl(L)(4)](2+) increase in the order py < isn < 4-acpy. The stretching band frequency. v(NO), of the nitrosyl complexes ranges from 1913 to 1852 cm(-1) indicating a nitrosonium character for the NO ligand. Due to the large pi-acceptor ability of the equatorial ligands, the coordinated water is much more acidic in the water soluble trans-[Ru(NO)(H(2)O)(py)(4)](3+) than in trans-[Ru(NO)(H(2)O)(NH(3))(4)](3+) (C) 2009 Elsevier B.V. All rights reserved.

The Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome (TRA.CER) trial: study design and rationale

Background The protease-activated receptor 1 (PAR-1), the main platelet receptor for thrombin, represents a novel target for treatment of arterial thrombosis, and SCH 530348 is an orally active, selective, competitive PAR-1 antagonist. We designed TRA.CER to evaluate the efficacy and safety of SCH 530348 compared with placebo in addition to standard of care in patients with non-ST-segment elevation (NSTE) acute coronary syndromes (ACS) and high-risk features. Trial design TRA.CER is a prospective, randomized, double-blind, multicenter, phase III trial with an original estimated sample size of 10,000 subjects. Our primary objective is to demonstrate that SCH 530348 in addition to standard of care will reduce the incidence of the composite of cardiovascular death, myocardial infarction (MI), stroke, recurrent ischemia with rehospitalization, and urgent coronary revascularization compared with standard of care alone. Our key secondary objective is to determine whether SCH 530348 will reduce the composite of cardiovascular death, MI, or stroke compared with standard of care alone. Secondary objectives related to safety are the composite of moderate and severe GUSTO bleeding and clinically significant TIMI bleeding. The trial will continue until a predetermined minimum number of centrally adjudicated primary and key secondary end point events have occurred and all subjects have participated in the study for at least I year. The TRA.CER trial is part of the large phase III SCH 530348 development program that includes a concomitant evaluation in secondary prevention. Conclusion TRA.CER will define efficacy and safety of the novel platelet PAR-1 inhibitor SCH 530348 in the treatment of high-risk patients with NSTE ACS in the setting of current treatment strategies. (Am Heart J 2009; 158:327-34.)

Posterior reversible encephalopathy syndrome after liver transplantation in children: A rare complication related to calcineurin inhibitor effects

PRES is a neuroclinical and radiological syndrome that results from treatment with calcineurin inhibitor immunosuppressives. Severe hypertension is commonly present, but some patients may be normotensive. We report herein two children who received liver transplants, as treatment for biliary atresia in the first case and for Alagille`s syndrome in the second one. In the early postoperative, both patients presented hypertension and seizures. In both cases, the image findings suggested the diagnosis of PRES. The CT scan showed alterations in the posterior area of the brain, and brain MRI demonstrated parietal and occipital areas of high signal intensity. Both children were treated by switching the immunosuppressive regimen and controlling arterial blood pressure. They displayed full recuperation without any neurologic sequelae. Probably, the pathophysiology of PRES results from sparse sympathetic innervation of the vertebrobasilar circulation, which is responsible for supplying blood to the posterior areas of the brain. In conclusion, all liver-transplanted children who present with neurological symptoms PRES should be considered in the differential diagnosis, although this is a rare complication. As treatment, we recommend rigorous control of arterial blood pressure and switching the immunosuppressive regimen.

Low mRNA Expression of the Apoptosis-Related Genes CASP3, CASP8, and FAS Is Associated With Low Induction Treatment Response in Childhood Acute Lymphoblastic Leukemia (ALL)

Background. Defects in apoptosis signaling have been considered to be responsible for treatment failure in many types of cancer, although with controversial results. The objective of the present study was to assess the expression profile of key apoptosis-related genes in terms of clinical and biological variables and of the survival of children with acute lymphoblastic leukemia (ALL). Procedure. The levels of mRNA expression of the apoptosis-related genes CASP3, CASP8, CASP9, FAS, and BCL2 were analyzed by quantitative real-time PCR in consecutive samples from 139 consecutive children with ALL at diagnosis treated by the Brazilian protocol (GBTLI-ALL 99). Gene expression levels and clinical and biological features were compared by the Mann-Whitney test. Event-free survival (EFS) was calculated by Kaplan-Meier plots and log-rank test. Results. A significant correlation was detected between CASP3, CASP8, CASP9, and FAS expression levels (P<0.01) in ALL samples. Higher levels of BCL2 were significantly associated with white blood cell (WBC) count <50,000/mm(3) at diagnosis (P=0.01) and low risk group classification (P=0.008). Lower expression levels of CASP3, CASP8 and FAS gene were associated with a poor response at day 7 according the GBTLI-ALL 99 protocol (P=0.03, P=0.02 and P=0.008, respectively). There was a relationship between FAS gene expression lower than the 75th percentile and lower 5-year EFS (P=0.02). Conclusion. These findings suggest an association between lower expression levels of the pro-apoptotic genes and a poor response to induction therapy at day 7 and prognosis in childhood ALL. Pediatr Blood Cancer 2010;55:100-107. (C) 2010 Wiley-Liss, Inc.

Ozone formation potentials of volatile organic compounds and ozone sensitivity to their emission in the megacity of Sao Paulo, Brazil

In the present study, a three-dimensional Eulerian photochemical model was employed to estimate the impact that organic compounds have on tropospheric ozone formation in the Metropolitan Area of Sao Paulo (MASP). In the year 2000, base case simulations were conducted in two periods: August 22-24 and March 13-15. Based on the pollutant concentrations calculated by the model, the correlation coefficient relative to observations for ozone ranged from 0.91 to 0.93 in both periods. In the simulations employed to evaluate the ozone potential of individual VOCs, as well as the sensitivity of ozone to the VOC/NO(x) emission ratio, the variation in anthropogenic emissions was estimated at 15% (according to tests performed previously variations of 15% were stable). Although there were significant differences between the two periods, ozone concentrations were found to be much more sensitive to VOCs than to NO(x) in both periods and throughout the study domain. In addition, considering their individual rates of emission from vehicles, the species/classes that were most important for ozone formation were as follows: aromatics with a kOH>2x 10(4) ppm(-1) min(-1); olefins with a kOH 7 x 10(4) ppm(-1) min(-1); olefins with a kOH 7 x 10(4) ppm(-1) min(-1); ethene; and formaldehyde, which are the principal species related to the production, transport, storage and combustion of fossil fuels.

The Cariris Velhos tectonic event in Northeast Brazil

The Borborema Province in northeastern South America is a typical Brasiliano-Pan-African branching system of Neoproterozoic orogens that forms part of the Western Gondwana assembly. The province is positioned between the Sao Luis-West Africa craton to the north and the Sao Francisco (Congo-Kasai) craton to the south. For this province the main characteristics are (a) its subdivision into five major tectonic domains, bounded mostly by long shear zones, as follows: Medio Coreau, Ceara Central, Rio Grande do Norte, Transversal, and Southern; (b) the alternation of supracrustal belts with reworked basement inliers (Archean nuclei + Paleoproterozoic belts); and (c) the diversity of granitic plutonism, from Neoproterozoic to Early Cambrian ages, that affect supracrustal rocks as well as basement inliers. Recently, orogenic rock assemblages of early Tonian (1000-920 Ma) orogenic evolution have been recognized, which are restricted to the Transversal and Southern domains of the Province. Within the Transversal Zone, the Alto Pajeu terrane locally includes some remnants of oceanic crust along with island arc and continental arc rock assemblages, but the dominant supracrustal rocks are mature and immature pelitic metasedimentary and metavolcaniclastic rocks. Contiguous and parallel to the Alto Pajeu terrane, the Riacho Gravata subterrane consists mainly of low-grade metamorphic successions of metarhythmites, some of which are clearly turbiditic in origin, metaconglomerates, and sporadic marbles, along with interbedded metarhyolitic and metadacitic volcanic or metavolcaniclastic rocks. Both terrane and subterrane are cut by syn-contractional intrusive sheets of dominantly peraluminous high-K calc-alkaline, granititic to granodioritic metaplutonic rocks. The geochemical patterns of both supracrustal and intrusive rocks show similarities with associations of mature continental arc volcano-sedimentary sequences, but some subordinate intra-plate characteristics are also found. In both the Alto Pajeu and Riacho Gravata terranes, TIMS and SHRIMP U-Pb isotopic data from zircons from both metavolcanic and metaplutonic rocks yield ages between 1.0 and 0.92 Ga, which define the time span for an event of orogenic character, the Cariris Velhos event. Less extensive occurrences of rocks of Cariris Velhos age are recognized mainly in the southernmost domains of the Province, as for example in the Polo Redondo-Maranco terrane, where arc-affinity migmatite-granitic and meta-volcano-sedimentary rocks show U-Pb ages (SHRIMP data) around 0.98-0.97 Ga. For all these domains, Sm-Nd data exhibit Tom model ages between 1.9 and 1.1 Ga with corresponding slightly negative to slightly positive epsilon(Nd)(t) values. These domains, along with the Borborema Province as a whole, were significantly affected by tectonic and magmatic events of the Brasiliano Cycle (0.7-0.5 Ga), so that it is possible that there are some other early Tonian rock assemblages which were completely masked and hidden by these later Brasiliano events. Cariris Velhos processes are younger than the majority of orogenic systems at the end of Mesoproterozoic Era and beginning of Neoproterozoic throughout the world, e.g. Irumide belt, Kibaride belt and Namaqua-Natal belt, and considerably younger than those of the youngest orogenic process (Ottawan) in the Grenvillian System. Therefore, they were probably not associated with the proposed assembly of Rodinia. We suggest, instead, that Cariris Velhos magmatism and tectonism could have been related to a continental margin magmatic arc, with possible back-arc associations, and that this margin may have been a short-lived (<100 m.y.) leading edge of the newly assembled Rodinia supercontinent. (C) 2009 Elsevier Ltd. All rights reserved.

Breastfeeding and non-nutritive sucking patterns related to the prevalence of anterior open bite in primary dentition

OBJECTIVE: Nutritional, immunological and psychological benefts of exclusive breastfeeding for the frst 6 months of life are unequivocally recognized. However, mothers should also be aware of the importance of breastfeeding for promoting adequate oral development. This study evaluated the association between breastfeeding and non-nutritive sucking patterns and the prevalence of anterior open bite in primary dentition. MATERIAL AND METHODS: Infant feeding and non-nutritive sucking were investigated in a 3-6 year-old sample of 1,377 children, from São Paulo city, Brazil. Children were grouped according to breastfeeding duration: G1 - non-breastfed, G2 - shorter than 6 months, G3 - interruption between 6 and 12 months, and G4 - longer than 12 months. Three calibrated dentists performed clinical examinations and classifed overbite into 3 categories: normal, anterior open bite and deep bite. Chi-square tests (p<0.05) with odds ratio (OR) calculation were used for intergroup comparisons. The impact of breastfeeding and non-nutritive sucking on the prevalence of anterior open bite was analyzed using binary logistic regression. RESULTS: The prevalence estimates of anterior open bite were: 31.9% (G1), 26.1% (G2), 22.1% (G3), and 6.2% (G4). G1 would have signifcantly more chances of having anterior open bite compared with G4; in the total sample (OR=7.1) and in the subgroup without history of non-nutritive sucking (OR=9.3). Prolonging breastfeeding for 12 months was associated with a 3.7 times lower chance of having anterior open bite. In each year of persistence with non-nutritive sucking habits, the chance of developing this malocclusion increased in 2.38 times. CONCLUSIONS: Breastfeeding and non-nutritive sucking durations demonstrated opposite effects on the prediction of anterior open bite. Non-breastfed children presented signifcantly greater chances of having anterior open bite compared with those who were breastfed for periods longer than 12 months, demonstrating the benefcial infuence of breastfeeding on dental occlusion.

Dental caries and related factors in Brazilian children from fluoridated and non-fluoridated areas

PURPOSE: To compare the caries prevalence, saliva buffering capacity (SBC), oral hygiene (OH), dietary habits, family income (FI) and frequency of visits to a dental office (Do) between Brazilian children living in areas with and without fluoridated public water supply. METHODS: Forty-six 5-7-year-old preschoolers were selected in Itatiba, SP, Brazil; 19 were from a fluoridated area, and 27 were from a non-fluoridated area. The caries index was determined according to the World Health Organization criteria, and the SBC was assessed by titration with hydrochloric acid. The FI, frequency of OH and visits to Do were estimated by questionnaire. The dietary habits were assessed with a diet chart. The differences between the groups were analyzed with Mann-Whitney-U tests (α=0.05). RESULTS: Children from the non-fluoridated area showed significantly higher dmft/DMFT than those from the fluoridated area, but they showed significantly lower SBC, OH frequency and FI. No significant differences were observed between the areas for dietary habits and visits to Do. CONCLUSION: Children from fluoridated areas showed higher salivary buffering capacity, family income and oral hygiene frequency as well as lower caries prevalence, supporting the beneficial effect of fluoride in the tap water for caries prevention.

Overview of the taxonomy and of the major secondary metabolites and their biological activities related to human health of the Laurencia complex (Ceramiales, Rhodophyta) from Brazil

In Brazil, the Laurencia complex is represented by twenty taxa: Laurencia s.s. with twelve species, Palisada with four species (including Chondrophycus furcatus now that the proposal of its transference to Palisada is in process), and Osmundea and Yuzurua with two species each. The majority of the Brazilian species of the Laurencia complex have been phylogenetically analyzed by 54 rbcL sequences, including five other Rhodomelacean species as outgroups. The analysis showed that the Laurencia complex is monophyletic with high posterior probability value. The complex was separated into five clades, corresponding to the genera: Chondrophycus, Laurencia, Osmundea, Palisada, and Yuzurua. A bibliographical survey of the terpenoids produced by Brazilian species showed that only six species of Laurencia and five of Palisada (including C. furcatcus) have been submitted to chemical analysis with 48 terpenoids (47 sesquiterpenes and one triterpene) isolated. No diterpenes were found. Of the total, 23 sesquiterpenes belong to the bisabolane class and eighteen to the chamigrene type, whose biochemical precursor is bisabolane, two are derived from lauranes and four are triquinols. Despite the considerable number of known terpenes and their ecological and pharmacological importance, few experimental biological studies have been performed. In this review, only bioactivities related to human health were considered.

Age polyethism in Plebeia emerina (Friese) (Hymenoptera: Apidae) colonies related to propolis handling

Stingless bees collect plant resins and make it into propolis, although they have a wider range of use for this material than do honey bees (Apis spp.). Plebeia spp. workers employ propolis mixed with wax (cerumen) for constructing and sealing nest structures, while they use viscous (sticky) propolis for defense by applying it onto their enemies. Isolated viscous propolis deposits are permanently maintained at the interior of their colonies, as also seen in other Meliponini species. Newly-emerged Plebeia emerina (Friese) workers were observed stuck to and unable to escape these viscous propolis stores. We examined the division of labor involved in propolis manipulation, by observing marked bees of known age in four colonies of P. emerina from southern Brazil. Activities on brood combs, the nest involucrum and food pots were observed from the first day of life of the marked bees. However, work on viscous propolis deposits did not begin until the 13th day of age and continued until the 56th day (maximum lifespan in our sample). Although worker bees begin to manipulate cerumen early, they seem to be unable to handle viscous propolis till they become older.

The mitochondrial genome of the stingless bee Melipona bicolor (Hymenoptera, Apidae, Meliponini): sequence, gene organization and a unique tRNA translocation event conserved across the tribe Meliponini

At present a complete mtDNA sequence has been reported for only two hymenopterans, the Old World honey bee, Apis mellifera and the sawfly Perga condei. Among the bee group, the tribe Meliponini (stingless bees) has some distinction due to its Pantropical distribution, great number of species and large importance as main pollinators in several ecosystems, including the Brazilian rain forest. However few molecular studies have been conducted on this group of bees and few sequence data from mitochondrial genomes have been described. In this project, we PCR amplified and sequenced 78% of the mitochondrial genome of the stingless bee Melipona bicolor (Apidae, Meliponini). The sequenced region contains all of the 13 mitochondrial protein-coding genes, 18 of 22 tRNA genes, and both rRNA genes (one of them was partially sequenced). We also report the genome organization (gene content and order), gene translation, genetic code, and other molecular features, such as base frequencies, codon usage, gene initiation and termination. We compare these characteristics of M. bicolor to those of the mitochondrial genome of A. mellifera and other insects. A highly biased A+T content is a typical characteristic of the A. mellifera mitochondrial genome and it was even more extreme in that of M. bicolor. Length and compositional differences between M. bicolor and A. mellifera genes were detected and the gene order was compared. Eleven tRNA gene translocations were observed between these two species. This latter finding was surprising, considering the taxonomic proximity of these two bee tribes. The tRNA Lys gene translocation was investigated within Meliponini and showed high conservation across the Pantropical range of the tribe.