Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto

About: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto is a based out in . It is known for research contribution in the topics: Population & Genus. The organization has 2143 authors who have published 3674 publications receiving 71071 citations. The organization is also known as: FFCLRP & FFCLRP-USP.

Identification of Africanized honey bees through wing morphometrics: two fast and efficient procedures

Abstract: Currently available morphometric and genetic techniques that can accurately identify African- ized honey bees are both costly and time consuming. We tested two new morphometric techniques (ABIS - Automatic Bee Identification System and geometric morphometrics analysis) on samples consisting of digital images of five worker forewings per colony. These were collected from 394 colonies of Africanized bees from all over Brazil and from colonies of African bees, Apis mellifera scutellata (n = 14), and Euro- pean bees, A. m. ligustica (n = 10), A. m. mellifera (n = 15), and A. m. carnica (n=15) from the Ruttner collection in Oberursel, Germany (preserved specimens). Both methods required less than five minutes per sample, giving more than 99% correct identifications. There was just one misidentification (based on ge- ometric morphometrics analysis) of Africanized bees compared with European subspecies, which would be the principal concern in newly-colonized areas, such as the southern USA. These new techniques are inexpensive, fast and precise. Africanized honey bee / morphometrics / geometric morphometrics analysis / ABIS / Apis mellifera / automatic identification

A Comprehensive Study of Polymorphic Sites along the HLA-G Gene: Implication for Gene Regulation and Evolution

Abstract: HLA-G molecule plays an important role on immune response regulation and has been implicated on the inhibition of T and natural killer cell cytolytic function and inhibition of allogeneic T-cell proliferation. Due to its immune-modulator properties, the HLA-G gene expression has been associated with the outcome of allograft and of autoimmune, infectious, and malignant disorders. Several lines of evidence indicate that HLA-G polymorphisms at the 5#-upstream regulatory region (5# URR) and 3#-untranslated region (3# UTR) may influence the HLA-G expression levels. Because Brazilians represent one of the most heterogeneous populations in the world with the widest HLA-G coding region variability already detected among the studied populations, a high level of variability and haplotype diversity would be expected in Brazilians. On this basis, the 5# URR, coding, and 3# UTR variability were evaluated in a Brazilian series consisting of 100 healthy bone marrow donors, as well as the linkage disequilibrium pattern along the gene and the extended haplotypes encompassing several gene segment variations. The HLA-G locus seems to present six different HLA-G lineages showing functional variations mainly in nucleotides of the regulatory regions. Differences were observed at the 5# URR in positions that either coincide with or are close to transcription factor–binding sites and at the 3# UTR mainly in positions that have already been reported to influence HLA-G mRNA availability. We report several lines of evidence for balancing selection acting on the regulatory regions, which may indicate that these HLA-G lineages may be related to the differential HLA-G expression profiles.

Purification and properties of a thermostable extracellular β- D -xylosidase produced by a thermotolerant Aspergillus phoenicis

Abstract: A β-D-xylosidase was purified from cultures of a thermotolerant strain of Aspergillus phoenicis grown on xylan at 45°C. The enzyme was purified to homogeneity by chromatography on DEAE-cellulose and Sephadex G-100. The purified enzyme was a monomer of molecular mass 132 kDa by gel filtration and SDS-PAGE. Treatment with endoglycosidase H resulted in a protein with a molecular mass of 104 kDa. The enzyme was a glycoprotein with 43.5% carbohydrate content and exhibited a pI of 3.7. Optima of temperature and pH were 75°C and 4.0–4.5, respectively. The activity was stable at 60°C and had a K m of 2.36 mM for p-nitrophenyl-β-D-xylopiranoside. The enzyme did not exhibit xylanase, cellulase, galactosidase or arabinosidase activities. The purified enzyme was active against natural substrates, such as xylobiose and xylotriose. Journal of Industrial Microbiology & Biotechnology (2001) 26, 156–160.

Functional characterization of the Aspergillus fumigatus CRZ1 homologue, CrzA.

Abstract: The protein phosphatase calcineurin is an important mediator connecting calcium-dependent signalling to various cellular responses in multiple organisms. In fungi calcineurin acts largely through regulating Crz1p-like transcription factors. Here we characterize an Aspergillus fumigatus CRZ1 homologue, CrzA and demonstrate its mediation of cellular tolerance to increased concentrations of calcium and manganese. In addition to acute sensitivity to these ions, and decreased conidiation, the crzA null mutant suffers altered expression of calcium transporter mRNAs under high concentrations of calcium, and loss of virulence when compared with the corresponding complemented and wild-type strains. We use multiple expression analyses to probe the transcriptional basis of A. fumigatus calcium tolerance identifying several genes having calA and/or crzA dependent mRNA accumulation patterns. We also demonstrate that contrary to previous findings, the gene encoding the Aspergillus nidulans calcineurin subunit homologue, cnaA, is not essential and that the cnaA deletion mutant shares the morphological phenotypes observed in the corresponding A. fumigatus mutant, DeltacalA. Exploiting the A. nidulans model system, we have linked calcineurin activity with asexual developmental induction, finding that CrzA supports appropriate developmental induction in a calcineurin and brlA-dependent manner in both species.