Staminode of Jacaranda rugosa A.H. Gentry (Bignoniaceae) promotes functional specialization by ensuring signaling and mechanical fit to medium-sized bees

Organisms Diversity & Evolution - The floral traits in Bignoniaceae are claimed as precise determiners of specialized pollination systems. Here, we investigated how such floral traits ensure a...     

Phenotypic and genetic correlations for body structure scores (frame) with productive traits and index for CEIP classification in Nellore beef cattle

The present study was carried out to estimate both (co)variance components and genetic parameters for frame scores obtained using two methods (FRAME_GMA and FRAME_BIF) as well as phenotypic and genetic correlations with traits such as weaning weight, weight gain from weaning to yearling, scrotal circumference, muscle score, and an empiric index for animal classification for the Special Certificate of Identification and Production (CEIP). Data on 12,728 animals, raised in Southeastern Brazil, with ages from 490 to 610 days were analyzed. Estimates of heritability for FRAME_GMA and FRAME_BIF in multi-trait analysis were 0.28 and 0.24, respectively. Genetic correlation coefficients between frame scores and the growth trait were of medium magnitude, which indicates that genetic selection for weight resulted in undesirable responses, increasing the animals' frames. Small changes should be expected in the frame of animals that have been submitted to a genetic selection regarding muscle score and scrotal circumference. The low magnitude of phenotypic and genetic correlation between frame scores and the empirical selection index that classifies animals for CEIP, a Brazilian official certificate that recognizes the value of seedstock that is not registered at breeders associations, but is genetically evaluated, does not indicate important responses in giving a CEIP to animals that have been directly or indirectly selected for frame. Other studies must be performed to determine estimates of the genetic parameters for frame scores in other beef cattle populations.     

Population dynamics of Aceria guerreronis (Acari: Eriophyidae) and other mites associated with coconut fruits in Una, state of Bahia, northeastern Brazil

Aceria guerreronis Keifer is a major coconut pest in the Americas, Africa and some Asian countries, and occurs in high population levels in northeastern Brazil. The determination of the climatic conditions that favorably affect its population growth and the prevalence and abundance of predatory mites can promote more efficient control practices. Our objective was to evaluate the pattern of occurrence and population dynamics of A. guerreronis, their associated predators and other mites during a 2?year period in a hybrid coconut plantation in the municipality of Una, state of Bahia, northeastern Brazil. Monthly samples of fruits were taken from June 2008 to May 2010 for qualitative and quantitative evaluation of mites. Aceria guerreronis represented 99.9?% of the mites. An average density of 1,117 mites per fruit and a maximum of 23,596 mites per fruit indicated that the level of infestation can be high in Bahia. Bdella ueckermanni Hernandes, Daud and Feres was the most abundant and frequent predator. Population increase of A. guerreronis was directly related to the temperature rise and inversely related to both the increase of air relative humidity and rainfall. The highest population densities occurred from November to March. The largest A. guerreronis populations occurred in fruits with 32 and 48?% of damaged surface. The relationship between prevailing wind direction and incidence of A. guerreronis could not be corroborated or refuted.     

Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement

doi: 10.1111/j.1741‐2358.2010.00435.x
Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement Objective: To evaluate the Vickers hardness of different acrylic resins for denture bases with and without the addition of glass fibres. Background: It has been suggested that different polymerisation methods, as well as the addition of glass fibre (FV) might improve the hardness of acrylic. Materials and methods: Five types of acrylic resin were tested: Vipi Wave (VW), microwave polymerisation; Vipi Flash (VF), auto‐polymerisation; Lucitone (LT), QC20 (QC) and Vipi Cril (VC), conventional heat‐polymerisation, all with or without glass fibre reinforcement (GFR) and distributed into 10 groups (n = 12). Specimens were then submitted to Vickers hardness testing with a 25‐g load for 30 s. All data were submitted to anova and Tukey’s HSD test. Results: A significant statistical difference was observed with regard to the polymerisation method and the GFR (p < 0.05). Without the GFR, the acrylic resin VC presented the highest hardness values, and VF and LT presented the lowest. In the presence of GFR, VC resin still presented the highest Vickers hardness values, and VF and QC presented the lowest. Conclusions: The acrylic resin VC and VW presented higher hardness values than VF and QC resins. Moreover, GFR increased the Vickers hardness of resins VW, VC and LT.     

Effect of Moringa oleifera flower extract on larval trypsin and acetylcholinesterase activities in Aedes aegypti

Aedes aegypti control is crucial to reducing dengue fever. Aedes aegypti larvae have developed resistance to organophosporous insecticides and the use of natural larvicides may help manage larval resistance by increasing elements in insecticide rotation programs. Here, we report on larvicidal activity of Moringa oleifera flower extract against A. aegypti L(1), L(2), L(3), and L(4) as well as the effect of flower extract on gut trypsin and whole-larval acetylcholinesterase from L(4.) In addition, the heated flower extract was investigated for larvicidal activity against L(4) and effect on larval gut trypsin. Moringa oleifera flower extract contains a proteinaceous trypsin inhibitor (M. oleifera flower trypsin inhibitor, MoFTI), triterpene (β-amyrin), sterol (β-sitosterol) as well as flavonoids (kaempferol and quercetin). Larvicidal activity was detected against L(2), L(3), and L(4) (LC(50) of 1.72%, 1.67%, and 0.92%, respectively). Flower extract inhibited L(4) gut trypsin (MoFTI K(i) = 0.6 nM) and did not affect acetylcholinesterase activity. In vivo assay showed that gut trypsin activity from L(4) treated with M. oleifera flower extract decreased over time (0-1,440 min) and was strongly inhibited (98.6%) after 310 min incubation; acetylcholinesterase activity was not affected. Thermal treatment resulted in a loss of trypsin inhibitor and larvicidal activities, supporting the hypothesis that flower extract contains a proteinaceous trypsin inhibitor that may be responsible for the deleterious effects on larval mortality.     

Comparative genomic analysis of three strains of Ehrlichia ruminantium reveals an active process of genome size plasticity

Ehrlichia ruminantium is the causative agent of heartwater, a major tick-borne disease of livestock in Africa that has been introduced in the Caribbean and is threatening to emerge and spread on the American mainland. We sequenced the complete genomes of two strains of E. ruminantium of differing phenotypes, strains Gardel (Erga; 1,499,920 bp), from the island of Guadeloupe, and Welgevonden (Erwe; 1,512,977 bp), originating in South Africa and maintained in Guadeloupe in a different cell environment. Comparative genomic analysis of these two strains was performed with the recently published parent strain of Erwe (Erwo) and other Rickettsiales (Anaplasma, Wolbachia, and Rickettsia spp.). Gene order is highly conserved between the E. ruminantium strains and with A. marginale. In contrast, there is very little conservation of gene order with members of the Rickettsiaceae. However, gene order may be locally conserved, as illustrated by the tuf operons. Eighteen truncated protein-encoding sequences (CDSs) differentiate Erga from Erwe/Erwo, whereas four other truncated CDSs differentiate Erwe from Erwo. Moreover, E. ruminantium displays the lowest coding ratio observed among bacteria due to unusually long intergenic regions. This is related to an active process of genome expansion/contraction targeted at tandem repeats in noncoding regions and based on the addition or removal of ca. 150-bp tandem units. This process seems to be specific to E. ruminantium and is not observed in the other Rickettsiales.     

Photosynthetic parameters of young Brazil nut (<Emphasis Type="Italic">Bertholletia excelsa</Emphasis> H. B.) plants subjected to fertilization in a degraded area in Central Amazonia

In an experimental site for reforestation of degraded area, three-year-old plants of Bertholletia excelsa Humb. & Bonpl. were subjected to different fertilization treatments: T0 = unfertilized control, T1 = green fertilization (branches and leaves) and T2 = chemical fertilization. Higher net photosynthetic rates (P _N) were observed in T1 [13.2±1.0 μmol(CO₂) m⁻² s⁻¹] compared to T2 [8.0±1.8 μmol(CO₂) m⁻² s⁻¹] and T0 [4.8±1.3 μmol(CO₂) m⁻² s⁻¹]. Stomatal conductance (g _s), transpiration rate (E) and water use efficiency (WUE) of individuals of T1 and T2 did not differ significantly, however, they were by 88, 55 and 63%, respectively, higher in T1 than in the control. The mean values of variable fluorescence (F_v), performance index (P.I.) and total chlorophyll [Chl (a+b)] were higher in T1. Our results indicate that green fertilization improves photosynthetic structure and function in plants of B. excelsa in young phase.     

2-Benzoylpyridine-N(4)-tolyl thiosemicarbazones and their palladium(II) complexes: Cytotoxicity against leukemia cells

The palladium(II) complexes [Pd(2Bz4oT)Cl], [Pd(2Bz4mT)Cl], and [Pd(2Bz4pT)Cl] were prepared with N(4)-ortho- (H2Bz4oT) N(4)-meta- (H2Bz4mT) and N(4)-para- (H2Bz4pT) tolyl-thiosemicarbazones derived from 2-benzoylpyridine. The free thiosemicarbazones proved to be highly cytotoxic against Jurkat, HL60 and the resistant HL60.Bcl-X_L leukemia cell lines at nanomolar concentrations, but were much less cytotoxic to HepG2 human hepatoma cells. Upon coordination to palladium(II) the cytotoxic activity against all studied cell lines decreases. However, the high cytotoxicity of the free thiosemicarbazones against leukemia, together with their hepatotoxic profile similar to that of cisplatin suggest that N(4)-tolyl thiosemicarbazones have potential as chemotherapeutic drug candidates.     

Binary and ternary inclusion complexes of finasteride in HPβCD and polymers: Preparation and characterization

The aim of this study was to determine whether inclusion complexes between 2-hydroxypropyl-β-cyclodextrin (HPβCD) and finasteride (FIN) are formed, and to characterize these. Equimolar FIN/HPβCD solid systems in the presence or absence of 0.1% (w/v) of polyvinylpyrrolidone K30 (PVP K30) or 0.3% of chitosan were prepared by coevaporation and freeze-drying methods. The systems were characterized by phase solubility, NMR, DSC, and XRD analysis. The results suggest that true binary and ternary inclusion complexes were formed.