Seasonality of pathogenic fungi in mites of rubber tree plantations adjacent to fragments of Cerrado

Fungos são os patógenos mais freqüentemente observados em populações de ácaros, auxiliando o controle destes em diferentes culturas. Vinte e cinco amostras de folhas foram coletadas de cultivos de seringueiras vizinhas a dois fragmentos de vegetação de Cerrado. em cada seringal, 25 plantas foram selecionadas para coletas e sete folhas ao redor da copa foram coletadas até a altura de sete a oito metros do solo. Aproximadamente 250 indivíduos de Calacarus heveae Feres, Phyllocoptruta seringueirae Feres e Tenuipalpus heveae Baker, coletados aleatoriamente, foram montados. Hirsutella thompsonii Fisher foi observado nas três espécies de ácaros e T. heveae foi a espécie mais infectada. Os maiores níveis de infecção ocorreram de novembro a fevereiro (estação chuvosa). Na estação seca, os níveis de infecção ficaram abaixo dos 5%. H. thompsonii tem potencial para ser usado como micoacaricida na estação chuvosa.

Probing the binding of the coumarin drugs using peptide fragments of DNA gyrase B protein

Bacterial DNA gyrase, has been identified as the target of several antibacterial agents, including the coumarin drugs. The coumarins inhibit the gyrase action by competitive binding to the ATP-binding site of DNA gyrase B (GyrB) protein. The high in vitro inhibitory potency of coumarins against DNA gyrase reactions has raised interest in studies on coumarin-gyrase interactions. In this context, a series of low-molecular weight peptides, including the coumarin resistance-determining region of subunit B of Escherichia coli gyrase, has been designed and synthesized. The first peptide model was built using the natural fragment 131-146 of GyrB and was able to bind to novobiocin (K a = 1.8 ± 0.2 × 105/M) and ATP (Ka = 1.9 ± 0.4 × 103/M). To build the other sequences, changes in the Arg136 residue were introduced so that the binding to the drug was progressively reduced with the hydrophobicity of this residue (Ka = 1.3 ± 0.1 × 105/M and 1.0 ± 0.2 × 105/M for Ser and His, respectively). No binding was observed for the change Arg136 to Leu. In contrast, the binding to ATP was not altered, independently of the changes promoted. On the contrary, for peptide-coumarin and peptide-ATP complexes, Mg2+ appears to modulate the binding process. Our results demonstrate the crucial role of Arg 136 residue for the stability of coumarin-gyrase complex as well as suggest a different binding site for ATP and in both cases the interactions are mediated by magnesium ions. Copyright Blackwell Munksgaard, 2005.

The use of fragments of thin veneers as a restorative therapy for anterior teeth disharmony: A case report with 3 years of follow-up

Aim: The present case report described the use of contact lens of thin porcelain veneers as a restorative therapy to solve anterior teeth disharmony. Background: Fragments of thin veneers are minimally invasive restorations with little or no dental preparation and present thickness ranging from 0.2 to 0.5 mm. They are used in case of diastema closure, small changes of teeth, color and restoration of teeth with small fractures. Case report: A 25-year-old man was admitted at a dental clinic complaining about the diastema presence on the upper anterior teeth. Patient was referred to an orthodontic treatment in order to provide better distribution of the diastemas and harmonious proportion of the teeth. Afterwards, contact lens of thin porcelain veneers were fabricated on the six upper anterior teeth. Conclusion: Based on the outcomes of this clinical report, we considered the use of fragments of thin veneers as a successful treatment option after 3 years of follow-up. Clinical significance: The fragments of thin veneers have been established to be an interesting alternative to esthetically restore the anterior teeth with minimal invasiveness. However, since it is a new treatment modality, longitudinal studies are necessary to understand the material's behavior.

Mite (Acari; Arachnida) diversity of two native plants in fragments of a semideciduous seasonal forest in Brazil

Studies to determine mite species richness in natural environments are still scarce, and have been conducted mainly in tropical ecosystems. The aim of this study was to determine the species richness of mites on two common native plants in fragments of the semideciduous seasonal forest in the Northwest of São Paulo State, Brazil. In each of eight fragments, 10 specimens of Actinostemon communis (Euphorbiaceae) and 10 of Trichilia casaretti (Meliaceae) were selected and marked. In total, 124 species of mites belonging to 21 families were found on the two plants. Tarsonemidae had the highest diversity (34 species), followed by Phytoseiidae (31), Tetranychidae (9) and Tenuipalpidae (8). Species accumulation curves for the two sampled plants did not reach an asymptote, even with the large sampling effort. Hence, it is estimated that a greater sampling effort may lead to an increase in species richness compared with what was found in this study. The richness of this mite fauna suggests that preservation of these plant species is important to maintain the mite diversity in these forest fragments. © 2013 Taylor & Francis Group, LLC.

Bats (Mammalia: Chiroptera) in urban fragments of Maringá, Paraná, Brazil

Bat assemblages in two urban fragments of Maringá city, north of the state of Paraná, southern Brazil, were inventoried. These fragments, Parque do Ingá (48 ha) and Parque Florestal dos Pioneiros (59 ha), are located in a subtropical region covered by semideciduous Atlantic forest. Bats were sampled with mist-nets from August 2006 to July 2007, over 24 nights (12 hours a night), adding up to a total of 30,240 h.m2 of net effort. A total of 839 individuals were captured belonging to 10 species and four families. Artibeus lituratus was the most abundant species (66% of the sample). The observed richness represents 22% of the bat species recorded for the state, 24% of the bat species occurring in the seasonal semideciduous forest of Paraná, 26% of the species previously recorded in urban environments in Brazil, and 83.4% of the estimated richness by Jackknife 1 (n= 12 species). Studies that provide data on richness and abundance of bat species in urban fragments are becoming increasingly important, but are still poorly available in Brazil. This habitat is especially interesting because anthropogenic pressure can be harmful to bat assemblages, reducing their diversity. © 2013 Check List and Authors.