Genetic structure and mating system of Euterpe edulis Mart. populations: A comparative analysis using microsatellite and allozyme markers

A comparative study between microsatellite and allozyme markers was conducted on the genetic structure and mating system in natural populations of Euterpe edulis Mart. Three cohorts, including seedlings, saplings, and adults, were examined in 4 populations using 10 allozyme loci and 10 microsatellite loci. As expected, microsatellite markers had a much higher degree of polymorphism than allozymes, but estimates of multilocus outcrossing rate ((t) over cap (m) = 1.00), as well as estimates of genetic structure (F(IS), G(ST)), were similar for the 2 sets of markers. Estimates of R(ST), for microsatellites, were higher than those of GST, but results of both statistics revealed a close agreement for the genetic structure of the species. This study provides support for the important conclusion that allozymes are still useful and reliable markers to estimate population genetic parameters. Effects of sample size on estimates from hypervariable loci are also discussed in this paper.

A new variety of the weed Borreria densiflora DC. (Rubiaceae)

The weed, known commonly as vassourinha de botao (buttonweed), is present in several crops in northern and north-eastern Brazil. Its occurrence is common in sugarcane and soybean crops in the states of Goias, Tocantins, and Maranhao. However, there is no published information in the literature about its taxonomic classification. Thus, this research aimed to classify taxonomically this species in order to develop a classification key based on the morphological characteristics among varieties of Borreria densiflora DC., as well as to illustrate it and provide a palynological basis to classify this species as a new variety For the classification process, data from the literature, morphological characteristics, and palynological evidence were considered. In this article, we describe a new variety, B. densiflora DC. var. latifolia E.L. Cabral & Martins. The new variety possesses a terrestrial habitat and it is a simple perennial weed species. These results show the importance of an accurate identification, as well as an understanding of the evolutionary changes inherent to weeds (like intraspecific variability), breeding system, genetic potential, and ecological studies. Those factors are essential to the beginning of a long-term weed management strategy.

Surface Liming and Zinc Availability in a Long-Term Experiment under No-Till System

No-till (NT) system with crop rotation is one of the most effective strategies to improve agricultural sustainability in tropical and subtropical regions. To control soil acidity in NT, lime is broadcast on the surface without incorporation. The increase in soil pH due to surface liming may decrease zinc (Zn) availability and its uptake by crops. A field experiment was performed in Parana State, Brazil, on a loamy, kaolinitic, thermic Typic Hapludox to evaluate Zn bioavailability in a NT system after surface liming and re-liming. Dolomitic lime was surface applied on the main plots in July 1993 at the rates of 0, 2, 4, and 6 Mg ha-1. In June 2000, the main plots were divided in two subplots to study of the effect of surface re-liming at the rates of 0 and 3 Mg ha-1. The cropping sequence was soybean [Glycine max (L.) Merrill] (2001-2 and 2002-3), wheat (Triticum aestivum L.) (2003), soybean (2003-4), corn (Zea mays L.) (2004-5), and soybean (2005-6). Soil samples were collected at the following depths: 0-0.05, 0.05-0.10, and 0.10-0.20m, 10 years after surface liming and 3 years after surface re-liming. Soil Zn levels were extracted by four extractants: (i) 0.005molL-1 diethylenetriaminepentaacetic acid (DTPA) + 0.1molL-1 triethanolamine (TEA) + 0.01molL-1 calcium chloride (CaCl2) solution at pH7.3 (DTPA-TEA), (ii) 0.1molL-1 hydrochloric acid (HCl) solution, (iii) Mehlich 1 solution, and (iv) Mehlich 3 solution. Zinc concentrations in leaves and grains of soybean, wheat, and corn were also determined. Soil pH (0.01molL-1 CaCl2 suspension) varied from 4.4 to 6.1, at the 0- to 0.05-m depth, from 4.2 to 5.3 at the 0.05- to 0.10-m depth, and from 4.2 to 4.8 at the 0.10- to 0.20-m depth, after liming and re-liming. Zinc concentrations evaluated by DTPA-TEA, 0.1molL-1 HCl, Mehlich 1, and Mehlich 3 solutions were not changed as a result of lime rate application. Re-liming increased Zn concentrations extracted by 0.1molL-1 HCl at 0-0.05m deep and by DTPA-TEA at 0.05-0.10m deep. Surface-applied lime promoted a decrease in Zn concentrations of the crops, mainly in grains, because of increased soil pH at the surface layers. Regardless of the liming treatments, levels of Zn were sufficient to soybean, wheat, and corn nutrition under NT.

Changes in the genetic structure of Bacteria and microbial activity in an agricultural soil amended with tannery sludge

The application of tannery sludge to soils is a form of recycling; however, few studies have examined the impacts of this practice on soil microbial properties. We studied effects of two applications (2006 and 2007) of tannery sludge (with a low chromium content) on the structure of the bacterial community and on the microbial activity of soils. We fertilized an agricultural area in Rolandia, Parana state, Brazil with different doses of sludge based on total N content, which ranged from 0 to 1200 kg N ha(-1). Sludge remained on the soil surface for three months before being plowed. Soils were sampled seven times during the experiment. Bacterial community structure, assessed by denaturing gradient gel electrophoresis (DGGE), was modified by the application of tannery sludge. Soon after the first application, there was clear separation between the bacterial communities in different treatments, such that each dose of sludge was associated with a specific community. These differences remained until 300 days after application and also after the second sludge application, but 666 days after the beginning of the experiment no differences were found in the bacterial communities of the lowest doses and the control. The principal response curve (PRC) analysis showed that the first sludge application strongly stimulated biological activity even 300 days after application. The second application also stimulated activity, but at a lower magnitude and for a shorter time, given that 260 days after the second application there was no difference in biological activity among treatments. PRC also showed that the properties most influenced by the application of tannery sludge were enzymatic activities related to N cycling (asparaginase and urease). The redundancy analysis (RDA) showed that tannery sludge`s influence on microbial activity is mainly related to increases in inorganic N and soil pH. Results showed that changes in the structure of the bacterial community in the studied soils were directly related to changes of their biological activity. (C) 2010 Elsevier Ltd. All rights reserved.

Parametric correlation functions to model the structure of permanent environmental (co)variances in milk yield random regression models

The objective of the present study was to estimate milk yield genetic parameters applying random regression models and parametric correlation functions combined with a variance function to model animal permanent environmental effects. A total of 152,145 test-day milk yields from 7,317 first lactations of Holstein cows belonging to herds located in the southeastern region of Brazil were analyzed. Test-day milk yields were divided into 44 weekly classes of days in milk. Contemporary groups were defined by herd-test-day comprising a total of 2,539 classes. The model included direct additive genetic, permanent environmental, and residual random effects. The following fixed effects were considered: contemporary group, age of cow at calving (linear and quadratic regressions), and the population average lactation curve modeled by fourth-order orthogonal Legendre polynomial. Additive genetic effects were modeled by random regression on orthogonal Legendre polynomials of days in milk, whereas permanent environmental effects were estimated using a stationary or nonstationary parametric correlation function combined with a variance function of different orders. The structure of residual variances was modeled using a step function containing 6 variance classes. The genetic parameter estimates obtained with the model using a stationary correlation function associated with a variance function to model permanent environmental effects were similar to those obtained with models employing orthogonal Legendre polynomials for the same effect. A model using a sixth-order polynomial for additive effects and a stationary parametric correlation function associated with a seventh-order variance function to model permanent environmental effects would be sufficient for data fitting.

Relating MODIS vegetation index time-series with structure, light absorption and stem production of fast-growing Eucalyptus plantations

By allowing the estimation of forest structural and biophysical characteristics at different temporal and spatial scales, remote sensing may contribute to our understanding and monitoring of planted forests. Here, we studied 9-year time-series of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on a network of 16 stands in fast-growing Eucalyptus plantations in Sao Paulo State, Brazil. We aimed to examine the relationships between NDVI time-series spanning entire rotations and stand structural characteristics (volume, dominant height, mean annual increment) in these simple forest ecosystems. Our second objective was to examine spatial and temporal variations of light use efficiency for wood production, by comparing time-series of Absorbed Photosynthetically Active Radiation (APAR) with inventory data. Relationships were calibrated between the NDVI and the fractions of intercepted diffuse and direct radiation, using hemispherical photographs taken on the studied stands at two seasons. APAR was calculated from the NDVI time-series using these relationships. Stem volume and dominant height were strongly correlated with summed NDVI values between planting date and inventory date. Stand productivity was correlated with mean NDVI values. APAR during the first 2 years of growth was variable between stands and was well correlated with stem wood production (r(2) = 0.78). In contrast, APAR during the following years was less variable and not significantly correlated with stem biomass increments. Production of wood per unit of absorbed light varied with stand age and with site index. In our study, a better site index was accompanied both by increased APAR during the first 2 years of growth and by higher light use efficiency for stem wood production during the whole rotation. Implications for simple process-based modelling are discussed. (C) 2009 Elsevier B.V. All rights reserved.

Large-scale ecological restoration of high-diversity tropical forests in SE Brazil

The complex interactions among endangered ecosystems, landowners` interests, and different models of land tenure and use, constitute an important series of challenges for those seeking to maintain and restore biodiversity and augment the flow of ecosystem services. Over the past 10 years, we have developed a data-based approach to address these challenges and to achieve medium and large-scale ecological restoration of riparian areas on private lands in the state of Sao Paulo, southeastern Brazil. Given varying motivations for ecological restoration, the location of riparian areas within landholdings, environmental zoning of different riparian areas, and best-practice restoration methods were developed for each situation. A total of 32 ongoing projects, covering 527,982 ha, were evaluated in large sugarcane farms and small mixed farms, and six different restoration techniques have been developed to help upscale the effort. Small mixed farms had higher portions of land requiring protection as riparian areas (13.3%), and lower forest cover of riparian areas (18.3%), than large sugarcane farms (10.0% and 36.9%, respectively for riparian areas and forest cover values). In both types of farms, forest fragments required some degree of restoration. Historical anthropogenic degradation has compromised forest ecosystem structure and functioning, despite their high-diversity of native tree and shrub species. Notably, land use patterns in riparian areas differed markedly. Large sugarcane farms had higher portions of riparian areas occupied by highly mechanized agriculture, abandoned fields, and anthropogenic wet fields created by siltation in water courses. In contrast, in small mixed crop farms, low or non-mechanized agriculture and pasturelands were predominant. Despite these differences, plantations of native tree species covering the entire area was by far the main restoration method needed both by large sugarcane farms (76.0%) and small mixed farms (92.4%), in view of the low resilience of target sites, reduced forest cover, and high fragmentation, all of which limit the potential for autogenic restoration. We propose that plantations should be carried out with a high-diversity of native species in order to create biologically viable restored forests, and to assist long-term biodiversity persistence at the landscape scale. Finally, we propose strategies to integrate the political, socio-economic and methodological aspects needed to upscale restoration efforts in tropical forest regions throughout Latin America and elsewhere. (C) 2010 Elsevier BA/. All rights reserved.

Antioxidant status in rats after long-term intake of anthocyanins and ellagitannins from blackberries

BACKGROUND: This study reported the effects of the daily intake of anthocyanins and ellagitannins (ET) extracted from blackberries on the markers for oxidative status in healthy rats. RESULTS: The phenolic compounds were administered from three different extracts: an aqueous extract of blackberry (BJ) and its two derived fractions: anthocyanin-enriched (AF) and ET-enriched (EF) fractions. After 35 days` administration, the AF and EF extracts significantly reduced thiobarbituric acid reactive substance levels and increased glutathione levels in the liver, kidney and brain. Plasma antioxidant capacity increased only in the group that received AF. Antioxidant enzyme activity and expression did not follow a pattern of response varying according to the tissues and extracts. A significant increase in the catalase activity was observed only in the plasma of the groups administered anthocyanin-containing extracts, which were the BJ and AF groups. Glutathione peroxidase activity was significantly increased in the liver and brain after EF treatment, and the highest increase in its expression was observed in the livers and brains of rats that received AF and EF, respectively. CONCLUSION: The results demonstrate that long-term intake of anthocyanin and ET through diet affects antioxidant enzyme activity and expression, and enhances oxidative markers in healthy rats. (C) 2010 Society of Chemical Industry

Crystal structure of 1,2-bis(4-fluoro-2-methylphenyl)ditelluride, [Te(C7H6F)](2)

C14H12F2Te2, monoclinic, C12/c1 (no. 15), a = 23.650(2) angstrom, b = 7.792(1) angstrom, c = 7.556(1) angstrom, beta = 106.47(1)degrees, V = 1335.2 angstrom(3), Z = 4, R-gt(F) = 0.041, wR(ref)(F-2) = 0.123, T= 98 K.

Toxocariasis/cysticercosis seroprevalence in a long-term rural settlement, Sao Paulo, Brazil

Seroprevalence of Toxocara and Taenia solium and risk factors for infection with these parasites were explored in a long-term rural settlement in Sao Paula state, Brazil. An ELISA for the detection of anti-Toxocara IgG and IgE and anti-T. solium cysticerci was standardized using Toxocara excretory-secretory antigens (TES) obtained from the cultured second-stage larvae of T. canis and by vesicular fluid antigen from Taenia crassiceps cysticerci (VC). For cysticercosis, the reactive ELISA samples were assayed by Western blot using 18 kDa and 14 kDa proteins purified from VF. Out of 182 subjects, 25 (13.7%,) presented anti-Toxocora IgG and it positive correlation between total IgE and the reactive index of specific anti-TES IgE (P=0.0265) was found amongst the subjects found seropositive for anti-Toxocara IgG. In these individuals 38.0%. showed ocular manifestations. The frequency of anti-T. solium cysticerci confirmed by Western blot wits 0.6%, Seropositivity for Toxocara was correlated with low educational levels and the owning of dogs. Embryonated eggs of Toxocara spp. were found in 43.3% of the analysed areas.

Crystal structure of Trypanosoma cruzi dihydroorotate dehydrogenase from Y strain

Trypanosoma cruzi is the etiological agent of Chagas` disease, a pathogenesis that affects millions of people in Latin America. Here, we report the crystal structure of dihydroorotate dehydrogenase (DHODH) from T cruzi strain Y solved at 2.2 angstrom resolution. DHODH is a flavin mononucleotide containing enzyme, which catalyses the oxidation Of L-dihydroorotate to orotate, the fourth step and only redox reaction in the de novo biosynthesis of pyrimidine nucleotides. Genetic studies have shown that DHODH is essential for T cruzi survival, validating the idea that this enzyme can be considered an attractive target for the development of antichagasic drugs. In our work, a detailed analysis of T cruzi DHODH crystal structure has allowed us to suggest potential sites to be further exploited for the design of highly specific inhibitors through the technology of structure-based drug design. (c) 2008 Elsevier Inc. All rights reserved.

HPLC separation, NMR and QTOF/MS/MS structure elucidation of a prominent nitric oxide donor agent based on an isomeric composition of a nitrosyl ruthenium complex

A new and promising nitrosyl ruthenium complex, [Ru(NO)(bdqi-COOH)(terpy)](PF(6))(3), bdqi-COOH is 3,4-diiminebenzoic acid and terpy is 2,2`-terpyridine, has been synthesized as a NO donor agent. The procedure used for [Ru(NO)(bdqi-COOH)(terpy)](PF(6))(3) synthesis has, apparently, yielded the formation of two isomers in which the ligand bdqi-COOH appears to be coordinated in its reduced form (bdcat-COOH), which could have differences in their pharmacological properties. Therefore, it was intended to separate the two possible isomers by high-performance liquid chromatography (HPLC) and to characterize them by high resolution mass spectrometry (QTOF MS) and by magnetic nuclear resonance spectroscopy (NMR). The results obtained by MS showed that the ESI-MS mass spectra of both HPLC column fractions, e.g. peak 1 and peak 2, are essentially equal, showing that both isomers display nearly identical gas-phase behavior with clusters of isotopologue ions centered at m/z 573, m/z 543 and m/z 513. Regarding the NMR analysis, the results showed that the positional isomerism is located in the bdqi-COOH ligand. From the observed results it can be concluded that the synthesis procedure that has been used results in the formation of two [Ru(terpy)(bdqi-COOH)NO](PF(6))(3) isomers. (c) 2009 Elsevier B.V. All rights reserved.

Trypanocidal structure-activity relationship for cis- and trans-methylpluviatolide

The trypanocidal activity of racemic mixtures of cis- and trans-methylpluviatolides was evaluated in vitro against trypomastigote forms of two strains of Trypanosoma cruzi, and in the enzymatic assay of T. cruzi gGAPDH. The cytotoxicity of the compounds was assessed by the MTT method using LLC-MK2 cells. The effect of the compounds on peroxide and NO production were also investigated. The mixture of the trans stereoisomers displayed trypanocidal activity (IC(50) similar to 89.3 mu M). Therefore, it was separated by chiral HPLC, furnishing the and (+) (-)-enantiomers. Only the (-)-enantiomer was active against the parasite (IC(50) similar to 18.7 mu M). Despite being inactive, the (+)-enantiomer acted as an antagonistic competitor. Trans-methylpluviatolide displayed low toxicity for LLC-MK(2) cells, with an IC(50) of 6.53 mM. Furthermore, methylpluviatolide neither inhibited gGAPDH activity nor hindered peroxide and NO production at the evaluated concentrations. (C) 2008 Elsevier Ltd. All rights reserved.

The effect of a novel crystallised bioactive glass-ceramic powder on dentine hypersensitivity: a long-term clinical study

P>The aim of this comparative clinical study was to evaluate a novel bioactive glass-ceramic (Biosilicate (R) 1-20 mu m particles) to treat dentine hypersensitivity (DH). Volunteers (n = 120 patients/ 230 teeth) received the following treatments: G1-Sensodyne (R), G2-SensiKill (R), G3-Biosilicate (R) incorporated in a 1% water-free-gel and G4-Biosilicate (R) mixed with distilled water at 1:10 ratio. G1 and G3 were applied at home, daily for 30 days; G2 and G4 were applied once a week by a dentist (four applications). A visual analogue scale (VAS) was employed to evaluate pain for each quadrant in one sensitive tooth at baseline, weekly during treatment and during a 6-month follow-up period. Dentine hypersensitivity values (G1/n = 52), (G2/n = 62), (G3/n = 59) and (G4/n = 59) were analysed with Kruskal-Wallis/Dunn tests. All the products were efficient in reducing DH after 4 weeks. Among the four materials tested, G4 demonstrated the best clinical performance and provided the fastest treatment to reduce DH pain. Distilled water proved to be an adequate vehicle to disperse Biosilicate (R). Low DH scores were maintained during the 6-month follow-up period. The hypothesis that the novel bioactive glass-ceramic may be an efficient treatment for DH was confirmed.

Schistosomicidal and trypanocidal structure-activity relationships for (+/-)-licarin A and its (-)- and (+)-enantiomers

(+/-)-Licarin A (1) was obtained by oxidative coupling, and its enantiomers, (-)-licarin A (2) and (+)-licarin A (3), were resolved by chiral HPLC. Schistosomicidal and trypanocidal activities of these compounds were evaluated in vitro against Schistosoma mansoni adult worms and trypomastigote forms of Trypanosoma cruzi. The racemic mixture (1) displayed significant schistosomicidal activity with an LC(50) value of 53.57 mu M and moderate trypanocidal activity with an IC(50) value of 127.17 mu M. On the other hand, the (-)-enantiomer (2), displaying a LC(50) value of 91.71 mu M, was more active against S. mansoni than the (+)-enantiomer (3), which did not show activity. For the trypanocidal assay, enantiomer 2 showed more significant activity (IC(50) of 23.46 mu M) than enantiomer 3, which showed an IC(50) value of 87.73 mu M. Therefore, these results suggest that (+/-)-licarin A (1) and (-)-licarin A (2) are promising compounds that could be used for the development of schistosomicidal and trypanocidal agents. (C) 2011 Elsevier Ltd. All rights reserved.