Virulence attributes and genetic variability of oral Candida albicans and Candida tropicalis isolates

The wide spectrum of candidiasis and its clinical importance encourage the research with the purpose of clarifying the mechanisms of pathogenicity and identification of virulence factors of Candida sp. Therefore, the aim of this study was to verify the adhesion capacity, protease activity and genotypic diversity of oral C. albicans and C. tropicalis isolates. The adhesion ability to the extracellular matrix glycoproteins laminin and fibronectin was evaluated using the ELISA technique. The research of proteases was carried out in agar plate containing bovine albumin and through a quantitative method in buffer solution containing haemoglobin. Intra and interspecies polymorphisms was verified through random amplified polymorphic DNA (RAPD) technique. All C. albicans and C. tropicalis isolates binded to immobilised laminin and fibronectin. Ca33 and Ct13 isolates had relative adhesion index significantly higher than the other isolates for both glycoproteins (P < 0.001). Protease activity was observed in all isolates of C. albicans using either the semi-quantitative or quantitative assay. The protease activity of C. tropicalis was better detected through the quantitative assay. The genotypic diversity by RAPD revealed a heterogeneous population in both species. Nevertheless, C. tropicalis presented higher genetic variability than C. albicans strains.

SPATIAL VARIABILITY OF THE RAINFALL EROSIVE POTENTIAL IN THE STATE OF MATO GROSSO DO SUL, BRAZIL

Information about rainfall erosivity is important during soil and water conservation planning. Thus, the spatial variability of rainfall erosivity of the state Mato Grosso do Sul was analyzed using ordinary kriging interpolation. For this, three pluviograph stations were used to obtain the regression equations between the erosivity index and the rainfall coefficient EI30. The equations obtained were applied to 109 pluviometric stations, resulting in EI30 values. These values were analyzed from geostatistical technique, which can be divided into: descriptive statistics, adjust to semivariogram, cross-validation process and implementation of ordinary kriging to generate the erosivity map. Highest erosivity values were found in central and northeast regions of the State, while the lowest values were observed in the southern region. In addition, high annual precipitation values not necessarily produce higher erosivity values.

GENETIC VARIABILITY OF SUGARCANE-ASSOCIATED DIAZOTROPHIC BACTERIA CAPABLE OF INORGANIC PHOSPHATE SOLUBILIZING

The sugarcane is a culture of great importance for the Brazilian agriculture. Every year this culture consumes great amounts of nitrogen and phosphate fertilizers. However, the use of plant growth-promoting bacteria can reduce the use of the chemical fertilizers, contributing to the economy and the environment conservation. So, the goal of this study was to select sugarcane-associated diazotrophic bacteria able to solubilize inorganic phosphate and to evaluate the genetic diversity of these bacteria. A total of 68 diazotrophic bacteria, leaf and root endophytic and rizoplane, of three sugarcane varieties. The selection of inorganic phosphate solubilizing diazotrophic bacteria was assayed by the solubilization index (SI) in solid medium containing insoluble phosphate. The genetic variability was analyzed by the BOX-PCR technique. The results showed that 74% of the diazotrophic strains were able to solubilize inorganic phosphate, presenting classes of different SI. The results showed that the vegetal tissue and the genotype plant influenced in the interaction between phosphate solubilizing diazotrophic bacteria and sugarcane plants. BOX-PCR revealed high genetic variability among the strains analyzed. So, sugarcane-associated diazotrophic bacteria express the capacity to solubilize inorganic phosphate and they present high genetic diversity.

A Transcriptomic View of the Proteome Variability of Newborn and Adult Bothrops jararaca Snake Venoms

Background: Snake bite is a neglected public health problem in communities in rural areas of several countries. Bothrops jararaca causes many snake bites in Brazil and previous studies have demonstrated that the pharmacological activities displayed by its venom undergo a significant ontogenetic shift. Similarly, the venom proteome of B. jararaca exhibits a considerable variation upon neonate to adult transition, which is associated with changes in diet from ectothermic prey in early life to endothermic prey in adulthood. Moreover, it has been shown that the Brazilian commercial antibothropic antivenom, which is produced by immunization with adult venom, is less effective in neutralizing newborn venom effects. On the other hand, venom gland transcripts of newborn snakes are poorly known since all transcriptomic studies have been carried out using mRNA from adult specimens. Methods/Principal Findings: Here we analyzed venom gland cDNA libraries of newborn and adult B. jararaca in order to evaluate whether the variability demonstrated for its venom proteome and pharmacological activities was correlated with differences in the structure of toxin transcripts. The analysis revealed that the variability in B. jararaca venom gland transcriptomes is quantitative, as illustrated by the very high content of metalloproteinases in the newborn venom glands. Moreover, the variability is also characterized by the structural diversity of SVMP precursors found in newborn and adult transcriptomes. In the adult transcriptome, however, the content of metalloproteinase precursors considerably diminishes and the number of transcripts of serine proteinases, C-type lectins and bradykinin-potentiating peptides increase. Moreover, the comparison of the content of ESTs encoding toxins in adult male and female venom glands showed some genderrelated differences. Conclusions/Significance: We demonstrate a substantial shift in toxin transcripts upon snake development and a marked decrease in the metalloproteinase P-III/P-I class ratio which are correlated with changes in the venom proteome complexity and pharmacological activities.

Spatio-temporal variability of sugarcane yield efficiency in the state of Sao Paulo, Brazil

The objective of this work was to assess the spatial and temporal variability of sugarcane yield efficiency and yield gap in the state of Sao Paulo, Brazil, throughout 16 growing seasons, considering climate and soil as main effects, and socioeconomic factors as complementary. An empirical model was used to assess potential and attainable yields, using climate data series from 37 weather stations. Soil effects were analyzed using the concept of production environments associated with a soil aptitude map for sugarcane. Crop yield efficiency increased from 0.42 to 0.58 in the analyzed period (1990/1991 to 2005/2006 crop seasons), and yield gap consequently decreased from 58 to 42%. Climatic factors explained 43% of the variability of sugarcane yield efficiency, in the following order of importance: solar radiation, water deficit, maximum air temperature, precipitation, and minimum air temperature. Soil explained 15% of the variability, considering the average of all seasons. There was a change in the correlation pattern of climate and soil with yield efficiency after the 2001/2002 season, probably due to the crop expansion to the west of the state during the subsequent period. Socioeconomic, biotic and crop management factors together explain 42% of sugarcane yield efficiency in the state of Sao Paulo.

Increased variability of motor cortical excitability to transcranial magnetic stimulation in migraine: a new clue to an old enigma

Increased, decreased or normal excitability to transcranial magnetic stimulation (TMS) has been reported in the motor (M1) and visual cortices of patients with migraine. Light deprivation (LD) has been reported to modulate M1 excitability in control subjects (CS). Still, effects of LD on M1 excitability compared to exposure to environmental light exposure (EL) had not been previously described in patients with migraine (MP). To further our knowledge about differences between CS and MP, regarding M1 excitability and effects of LD on M1 excitability, we opted for a novel approach by extending measurement conditions. We measured motor thresholds (MTs) to TMS, short-interval intracortical inhibition, and ratios between motor-evoked potential amplitudes and supramaximal M responses in MP and CS on two different days, before and after LD or EL. Motor thresholds significantly increased in MP in LD and EL sessions, and remained stable in CS. There were no significant between-group differences in other measures of TMS. Short-term variation of MTs was greater in MP compared to CS. Fluctuation in excitability over hours or days in MP is an issue that, until now, has been relatively neglected. The results presented here will help to reconcile conflicting observations.

In vitro analysis of the influence of surface treatment of dental implants on primary stability

Surface treatment interferes with the primary stability of dental implants because it promotes a chemical and micromorphological change on the surface and thus stimulates osseointegration. This study aimed to evaluate the effects of different surface treatments on primary stability by analyzing insertion torque (IT) and pullout force (PF). Eight samples of implants with different surface treatments (TS - external hexagon with acid surface treatment; and MS - external hexagon, machined surface), all 3.75 mm in diameter x 11.5 mm in length, were inserted into segments of artificial bones. The IT of each sample was measured by an electronic torquemeter, and then the pullout test was done with a universal testing machine. The results were subjected to ANOVA (p < 0.05), followed by Tukey's test (p < 0.05). The IT results showed no statistically significant difference, since the sizes of the implants used were very similar, and the bone used was not highly resistant. The PF values (N) were, respectively, TS = 403.75 +/- 189.80 and MS = 276.38 +/- 110.05. The implants were shown to be different in terms of the variables of maximum force (F = 4.401, p = 0.0120), elasticity in maximum flexion (F = 3.672, p = 0.024), and relative stiffness (F = 4.60, p = 0.01). In this study, external hexagonal implants with acid surface treatment showed the highest values of pullout strength and better stability, which provide greater indication for their use.

Variability of physicochemical properties of an epoxy resin sealer taken from different parts of the same tube

Baldi JV, Bernardes RA, Duarte MAH, Ordinola-Zapata R, Cavenago BC, Moraes JCS, de Moraes IG. Variability of physicochemical properties of an epoxy resin sealer taken from different parts of the same tube. International Endodontic Journal,similar to 45, 915920, 2012. Abstract Aim To analyse several physicochemical properties of AH Plus (Dentsply DeTrey, Konstanz, Germany), including setting time, flow, radiopacity and the degree of conversion (DC); and to correlate the results with the source of the material: from the beginning, middle or end of the tubes in which they were supplied. Methodology Three experimental groups were established for each property investigated. Group 1 corresponded to material taken from the beginning of tubes A and B; Group 2 corresponded to material taken from the middle of each tube; and group 3 corresponded to that from the end of each tube. The setting time, flow and radiopacity were studied according to American National Standards Institute/American Dental Association (ANSI/ADA) Specification 57. DC was determined from infrared spectra, which were recorded at 1-h intervals for the first 6 h; then, at 2-h intervals for the next 14 h; then, at 24 and 30 h. Data were analysed statistically by analysis of variance (anova), TukeyKramer, KruskalWallis and Dunn tests, with a significance level of 5%. Results Group 1 had a significantly longer setting time (2303 +/- 1058 min) (P < 0.05). Group 3 had the lowest flowability (30.0 +/- 0.7 mm) and the highest radiopacity (14.85 +/- 1.8 mm Al) (P < 0.05). No differences were found for the DC test (P > 0.05). Conclusion The results suggest that segregation occurs between the organic and inorganic components of AH Plus sealer, thereby changing the setting time, flow and radiopacity.

Genetic variability of banana with ornamental potential

The Musa germplasm collection at Embrapa Cassava and Fruits detains accessions from different sections of the Musa genus. The objective of the present study was to identify and morphologically characterize banana accessions from the banana germplasm with ornamental potential, as well as to quantify their genetic variability; and identify possible progenitors to be used in breeding aiming to achieve ornamental crossbreeds. The accessions were evaluated with the use of 32 morphological descriptors. Then, they were the following grouped into categories: landscape plants, cut flower, potted plants, and male inflorescence minifruits. The pre-selected accessions presented great genetic variability and ornamental potential for different uses. The accessions of the Rhodochlamys and Callimusa sections were selected to be used as landscape plants, cut flowers, potted plants, male inflorescence and minifruits. Most of the diploids from the Eumusa section evaluated in this study are indicated for the production of ornamental minifruits, except for 'Lidi' and Cici, which can also be indicated as landscape plants. The BB diploids have great potential for the use of the male inflorescence in floral arrangements, and did not offer any other indication.

STRUCTURE OF THE ELECTROMAGNETIC FIELD ALLOWING EXACT SOLUTION OF THE SCHRODINGER EQUATION IN SUPERPOSITION WITH AN AHARONOV-BOHM FIELD

A charged particle is considered in a complex external electromagnetic field. The field is a superposition of an Aharonov-Bohm field and some additional field. Here we describe all additional fields known up to the present time that allow exact solution of the Schrodinger equation in a complex field.

Molecular phylogeny and phenotypic variability of clinical and environmental strains of Aspergillus flavus

Aspergillus flavus is the second most common cause of aspergillosis infection in immunocompromised patients and is responsible for the production of aflatoxins. Little is known about the population structure of A. flavus, although recent molecular and phenotypic data seem to demonstrate that different genetic lineages exist within this species. The aim of this study was to carry out a morphological, physiological, and molecular analysis of a set of clinical and environmental isolates to determine whether this variability is due to species divergence or intraspecific diversity, and to assess whether the clinical isolates form a separate group. The amdS and omtA genes were more phylogenetically informative than the other tested genes and their combined analysis inferred three main clades, with no clear distinction between clinical and environmental isolates. No important morphological and physiological differences were found between the members of the different clades, with the exception of the assimilation of D-glucosamine, which differentiates the members of the clade II from the others. (C) 2012 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Linking origin of the electric field-assisted beta-PbF2 crystallization in lead oxyfluoroborate glasses below T (g) to simultaneous cathode/anode-compensated electrochemical reactions

Full validation of the electrochemical mechanisms so far postulated as driving force of electric field-assisted non-spontaneous crystallization development in given glasses has suffered experimental restrictions. In this work, we looked into origin of this phenomenon in lead oxyfluoroborate glasses, resulting in beta-PbF2 growth even below the corresponding glass transition temperatures, through achieving a systematic study of not only Pt,Ag/Glass/Ag,Pt- but also Pt,Ag/Glass/YSZ:PbF2/Ag,Pt-type cells, where YSZ:PbF2 represents a two-phase system (formed by Y2O3-doped ZrO2 and PbF2). It is demonstrated that crystallization induction in these glasses involves Pb2+ ions reduction at the cathode, the phenomenon being, however, confirmed only when the F- ions were simultaneously also able to reach the anode for oxidation, after assuring either a direct glass-anode contact or percolation pathways for free fluoride migration across the YSZ:PbF2 mixtures. A further support of this account is that the electrochemically induced beta-PbF2 phase crystallizes showing ramified-like microstructure morphology that arises, accordingly, from development of electroconvective diffusion processes under electric field action.

Spatio-temporal variability of sugarcane yield efficiency in the state of São Paulo, Brazil

The objective of this work was to assess the spatial and temporal variability of sugarcane yield efficiency and yield gap in the state of São Paulo, Brazil, throughout 16 growing seasons, considering climate and soil as main effects, and socioeconomic factors as complementary. An empirical model was used to assess potential and attainable yields, using climate data series from 37 weather stations. Soil effects were analyzed using the concept of production environments associated with a soil aptitude map for sugarcane. Crop yield efficiency increased from 0.42 to 0.58 in the analyzed period (1990/1991 to 2005/2006 crop seasons), and yield gap consequently decreased from 58 to 42%. Climatic factors explained 43% of the variability of sugarcane yield efficiency, in the following order of importance: solar radiation, water deficit, maximum air temperature, precipitation, and minimum air temperature. Soil explained 15% of the variability, considering the average of all seasons. There was a change in the correlation pattern of climate and soil with yield efficiency after the 2001/2002 season, probably due to the crop expansion to the west of the state during the subsequent period. Socioeconomic, biotic and crop management factors together explain 42% of sugarcane yield efficiency in the state of São Paulo.

Spatial variability of leaf nutrient contents in a drip irrigated citrus orchard

This study aimed to evaluate the spatial variability of leaf content of macro and micronutrients. The citrus plants orchard with 5 years of age, planted at regular intervals of 8 x 7 m, was managed under drip irrigation. Leaf samples were collected from each plant to be analyzed in the laboratory. Data were analyzed using the software R, version 2.5.1 Copyright (C) 2007, along with geostatistics package GeoR. All contents of macro and micronutrients studied were adjusted to normal distribution and showed spatial dependence.The best-fit models, based on the likelihood, for the macro and micronutrients were the spherical and matern. It is suggest for the macronutrients nitrogen, phosphorus, potassium, calcium, magnesium and sulfur the minimum distances between samples of 37; 58; 29; 63; 46 and 15 m respectively, while for the micronutrients boron, copper, iron, manganese and zinc, the distances suggests are 29; 9; 113; 35 and 14 m, respectively.

Spatial variability of soil fertility and its relationship with seed physiological potential in a soybean production area

The correlation of soil fertility x seed physiological potential is very important in the area of seed technology but results published with that theme are contradictory. For this reason, this study to evaluate the correlations between soil chemical properties and physiological potential of soybean seeds. On georeferenced points, both soil and seeds were sampled for analysis of soil fertility and seed physiological potential. Data were assessed by the following analyses: descriptive statistics; Pearson's linear correlation; and geostatistics. The adjusted parameters of the semivariograms were used to produce maps of spatial distribution for each variable. Organic matter content, Mn and Cu showed significant effects on seed germination. Most variables studied presented moderate to high spatial dependence. Germination and accelerated aging of seeds, and P, Ca, Mg, Mn, Cu and Zn showed a better fit to spherical semivariogram: organic matter, pH and K had a better fit to Gaussian model; and V% and Fe showed a better fit to the linear model. The values for range of spatial dependence varied from 89.9 m for P until 651.4 m for Fe. These values should be considered when new samples are collected for assessing soil fertility in this production area.