Free-ranging bats combine three different cognitive processes for roost localization

Oecologia - Animals have evolved different cognitive processes to localize crucial resources that are difficult to find. Relevant cognitive processes such as associative learning and spatial memory...     

Morphophysiological and Biochemical Responses of Lippia grata Schauer (Verbenaceae) to Water Deficit

Journal of Plant Growth Regulation - In the present study, we investigated the morphophysiological and biochemical responses of the species Lippia grata Schauer to water deficit. Plants from...     

Global and targeted proteomics in developing jack bean (Canavalia ensiformis) seedlings: an investigation of urease isoforms mobilization in early stages of development

Jack bean (Canavalia ensiformis) seeds are toxic for insects and the toxicity is due in part to an entomotoxic peptide enzymatically released from ureases in the midgut of susceptible insects. To characterize expression of urease isoforms in jack bean seed, particularly the more abundant urease isoform (JBU), quantitative proteomics was performed. Quiescent through 5-day germinating seeds were analyzed at 1-day intervals using a total proteomics approach (TPA) and also after co-immunoprecipitation (co-IP) with anti-JBU monoclonal antibodies. Jack bean proteins for TPA and co-IP were pre-fractionated by SDS-PAGE, segmented for in-gel trypsin digestion, and analyzed by liquid chromatography coupled to nanospray ionization tandem mass spectrometry (LC-MS/MS). Acquired MS(2) data were searched against a comprehensive plant database and the MEROPS peptidase database, in the absence of a jack bean EST database. Proteins detected in TPA were quantified by label-free spectral counting. A total of 234 and 106 non-redundant proteins were detected in TPA and co-IP, respectively. Mobilization of JBU was observed beginning 3-days after imbibition indicating that the entomotoxic peptide was not formed before this stage. A predicted urease isoform, JBURE-IIb, was detected in the co-IP study. Additionally, 46 plastid proteins, including RuBisCO and plastid ATPase were pulled down with JBU antibodies. These data shed new light on the behavior of urease isoforms during the early stages of plant development.     

Use of soybean vinasses as a germinant medium for a Geobacillus stearothermophilus ATCC 7953 sterilization biological indicator

A novel low-cost medium was developed from by-products and wastes from the ethanol agro-industry to replace commercial media in the production of a steam sterilization biological indicator (BI). Various recovery media were developed using soybean or sugarcane molasses and vinasse to prepare a self-contained BI. Media performance was evaluated by viability and heat resistance (D _121 °C value) according to regulatory standards. A medium produced with a soybean vinasse ratio of 1:70 (1.4%) (w/v) produced the results, with D _121 °C = 2.9 ± 0.5 min and Usk = 12.7 ± 2.1 min. The addition of 0.8% (w/v) yeast extract improved the germination of heat-damaged spores. The pH variation from 6.0 to 7.3 resulted in a gradual increase in the D _121 °C value. The absence of calcium chloride resulted in a decrease in germination, while no significant differences were observed with starch addition. Soybean vinasses may thus be used as the main component of a culture medium to substitute for commercial media in the production of self-contained biological indicators. The use of ethanol production waste in this biotechnological process realized a reliable performance, minimized the environmental impact, and decreased BI production costs while producing a high quality product.     

No relationship found between point heteroplasmy in mitochondrial DNA control region and age range,sex and haplogroup in human hairs

The analysis of heteroplasmy (presence of more than one type of mitochondrial DNA in an individual) is used as a tool in human identification studies, anthropology, and most currently in studies that relate heteroplasmy with longevity. The frequency of heteroplasmy and its correlation with age has been analyzed using different tissues such as blood, muscle, heart, bone and brain and in different regions of mitochondrial DNA, but this analysis had never been performed using hair samples. In this study, samples of hair were sequenced in order to ascertain whether the presence or not of heteroplasmy varied according to age, sex and origin of haplogroup individuals. The samples were grouped by age (3 groups), gender (male and female) and haplogroup of origin (European, African and Native American), and analyzed using the chi-square statistical test (χ²). Based in statistical results obtained, we conclude that there is no relationship between heteroplasmy and sex, age and haplogroup origin using hair samples.     

Effervescent tablets and ultrasonic devices against Candida and mutans streptococci in denture biofilm

doi: 10.1111/j.1741‐2358.2010.00378.x Effervescent tablets and ultrasonic devices against Candida and mutans streptococci in denture biofilm Objective: To evaluate the antimicrobial action of effervescent tablets and ultrasound on Candida spp. and mutans streptococci from denture biofilm. Background: It is not uncommon for edentulous patients to be elderly and find it difficult to brush their dentures. Hence, auxiliary methods are required for cleansing dentures as well as treating oral infections. Materials and methods: Seventy‐seven complete denture wearers were randomly assigned into four groups: (A) Brushing with water (control); (B) Effervescent tablets; (C) Ultrasonic device (Ultrasonic Cleaner, model 2840 D); (D) Effervescent tablets and ultrasonic device. All groups brushed their dentures with a specific brush and water, three times a day, before applying their treatments. Denture biofilm was collected at baseline and after 21 days. The samples were collected by brushing the dentures with saline and the detached microbial cells were quantified by plating. Counts [log (CFU+1) ml^?1] of total aerobes, Candida spp. and mutans streptococci were compared by one‐way anova or Kruskal–Wallis test (α = 0.05). Results: No significant difference was found among the methods from C. albicans (p = 0.76), C. tropicalis (p = 0.94) and C. glabrata (p = 0.80). Lower counts were found for methods B and D when compared with the other methods against mutans streptococci (p < 0.001). Method B showed lower total aerobic counts than A, whereas C and D showed intermediate results (p = 0.011). Conclusion: The effervescent tablets significantly reduced mutans streptococci and total aerobes from denture biofilm. However, they was not as effective against C. albicans. Ultrasonic cleansing presented a discrete antimicrobial effect and was less effective than the tablets for complete denture disinfection.     

Diversity of plasmids and transmission of high-level mupirocin mupA resistance gene in Staphylococcus haemolyticus

The coagulase-negative staphylococci are known for their ability to acquire resistance genes, which limits the choice of therapeutic options for the treatment of infections caused by these microorganisms. In this study, the diversity of high-level mupirocin resistance plasmids (Mup(R) ) was investigated in four strains of Staphylococcus haemolyticus belonging to different pulsed-field gel electrophoresis (PFGE) types or subtypes, isolated in a Brazilian hospital. These strains harbor the mupA gene in large plasmids. In addition, the presence of IS257 sequences flanking the mupA gene was also shown. Two isolates belonging to two different PFGE types exhibited a similar polymorphism for a fragment of the mupA gene and the closest proximal flanking copies of the IS257, suggesting horizontal transmission of S. haemolyticus mupirocin resistance plasmids in the environment and a role of this species as a reservoir of the mupA gene.     

The testosterone binding mechanism of an antibody derived from a naïve human scFv library

A testosterone binding scFv antibody was isolated from a naïve human library with a modest size of 10⁸ clones. The crystal structure of the Fab fragment form of the 5F2 antibody clone complexed with testosterone determined at 1.5 Å resolution shows that the hapten is bound deeply in the antibody binding pocket. In addition to the interactions with framework residues only CDR‐L3 and CDR‐H3 loops interact with testosterone and the heavy chain forms the majority of the contacts with the hapten. The testosterone binding site of the 5F2 antibody with a high abundance of aromatic amino acid residues shows similarity with an in vitro affinity matured antibody having around 300 times higher affinity. The moderate affinity of the 5F2 antibody originates from the different orientation of the hapten and few light chain contacts. This is the first three‐dimensional structure of a human steroid hormone binding antibody that has been isolated from a naïve human repertoire. Copyright © 2010 John Wiley & Sons, Ltd.