Evidence of Bartonella spp., Rickettsia spp. and Anaplasma phagocytophilum in domestic, shelter and stray cat blood and fleas, Portugal.

Thirty-two fleas were collected from 18 Lisboncats, 29 of which (90.6%) were C. felis, one (3.1%)was C. canis and two (6.3%) were unidentifiable. Only C. felis fleas were infected, six (40.0%)withB. clarridgeiae and six (40.0% ) with R. felis; three(20.0%) were co-infected. No positive result wasfound for A. phagocytophilum. The infection prev-alence of B. clarridgeiae was higher in domestic(43.8%) than in shelter cat fleas (28.6%). However,the infection rate of R. felis was higher in shelter(42.9%) than in domestic cat fleas (25.0%). Straycat fleas were only infected with R. felis (11.1%).Twenty-five cats (67.7%) were bacteraemic(Table 1). Twenty-one of them (84.0%) wereless than 1 year old, 15 (60.0%) were femalea nd 10 (40.0%) had no Bartonella spp. antibodies, one of which (10.0%) was more than 1 year old. The prevalence of Bartonella bacteraemia is higher in shelter (76.9%) than in domestic cats(68.2%) and all stray cats tested (n = 2) were positive

Random amplified polymorphic DNA profiles as a tool for the characterization of Brazilian keratitis isolates of the genus Acanthamoeba

The genus Acanthamoeba comprises free-living amebae identified as opportunistic pathogens of humans and other animal species. Morphological, biochemical and molecular approaches have shown wide genetic diversity within the genus. In an attempt to determine the genetic relatedness among isolates of Acanthamoeba we analyzed randomly amplified polymorphic DNA (RAPD) profiles of 11 Brazilian isolates from cases of human keratitis and 8 American type culture collection (ATCC) reference strains. We found that ATCC strains belonging to the same species present polymorphic RAPD profiles whereas strains of different species show very similar profiles. Although most Brazilian isolates could not be assigned with certainty to any of the reference species, they could be clustered according to pattern similarities. The results show that RAPD analysis is a useful tool for the rapid characterization of new isolates and the assessment of genetic relatedness of Acanthamoeba spp. A comparison between RAPD analyses and morphological characteristics of cyst stages is also discussed.Universidade de São PauloUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

A chromophoric study of 2-ethylhexyl p-methoxycinnamate

AbstractUltraviolet absorption spectra of 2-ethylhexyl p-methoxycinnamate have been recorded in different solvents and calculated using the time dependent density functional theory. The calculations were performed with the aid of B3LYP, PBE1PBE, M06, and PBEPBE functionals and 6-31+G(2d) basis set. The geometries were initially optimized using PM5 semiempirical method for the conformational search. The calculations of excited states were carried out using the time dependent with IEF-PCM solvent reaction field method. The experimental data were obtained in the wavelength range from 200 to 400nm using 10 different solvents. The TD-PBE1PBE method shows the best agreement to the experimental results

On the stability of the isoflux Darcy–Bénard problem with a generalised basic state

none5siThe scope of this study is to determine the conditions for the onset of the instability in a horizontal porous layer subject to isoflux boundary conditions and with an infinitely wide single–cell basic flow. When the circulation in the basic cellular flow is absent, one recovers the usual Darcy–Bénard conduction basic state. The governing parameters are the Rayleigh number associated with the uniform wall heat flux, and the dimensionless horizontal temperature gradient. The latter parameter controls the magnitude of the basic cellular circulation flow in the horizontal direction. The modal analysis of the instability is carried out numerically by employing a pseudo–spectral method, as well as the shooting method for the solution of the stability eigenvalue problem. Neutral stability and the critical conditions for the onset of the convective instability of the basic state are investigated.noneVayssiere Brandão, P.; Barletta, A.; Celli, M.; Alves, L.S. de B.; Rees, D.A.S.Vayssiere Brandão, P.; Barletta, A.; Celli, M.; Alves, L.S. de B.; Rees, D.A.S

The conservation of energy-momentum and the mass for the graviton

In this work we give special attention to the bimetric theory of gravitation with massive gravitons proposed by Visser in 1998. In his theory, a prior background metric is necessary to take in account the massive term. Although in the great part of the astrophysical studies the Minkowski metric is the best choice to the background metric, it is not possible to consider this metric in cosmology. In order to keep the Minkowski metric as background in this case, we suggest an interpretation of the energy-momentum conservation in Visser's theory, which is in accordance with the equivalence principle and recovers naturally the special relativity in the absence of gravitational sources. Although we do not present a general proof of our hypothesis we show its validity in the simple case of a plane and dust-dominated universe, in which the `massive term' appears like an extra contribution for the energy density.Comment: 9 pages, accepted for publishing in GR

Caracterização molecular de espécies de Enterococci resistentes à vancomicina oito anos após seu primeiro isolamento em São Paulo, Brasil

E. faecium was the first reported VRE species, carrying the vanA gene in Brazil. In spite of this, vancomycin-resistant E. faecalis has become the predominant species in Brazilian hospitals. The aim of this study was to evaluate the genetic relatedness of VREs isolated in a Brazilian teaching hospital eight years apart from its first isolation. We analyzed 38 VRE strains obtained from 81 surveillance cultures of patients admitted to the four largest intensive care units in Hospital São Paulo in February, 2006. Presence of the vanA gene was assayed by PCR and PFGE analysis was used for molecular characterization. All VRE strains carried the vanA gene. Two distinct clonal groups were observed among vancomycin-resistant E. faecalis. Vancomycin-resistant E. faecium belonged to five distinct clones were demonstrated by molecular typing. All of these clones were different from the first vancomycin-resistant enterococci clone isolated eight years ago in our hospital.E. faecium contendo o gene vanA foi a primeira espécie de VRE descrita, no Brasil. Apesar disto, E. faecalis resistente a vancomicina tem se tornado a espécie predominante nos hospitais brasileiros.O objetivo desse estudo foi avaliar a relação genética de VREs isolados em um hospital de ensino brasileiro após oito anos de seu primeiro isolamento. Analisamos 37 isolados de VRE obtidos de 81 culturas de vigilância de pacientes admitidos nas quatro maiores Unidades de Tratamento Intensivo em Fevereiro de 2006. A presença do gene vanA foi analisada por PCR e a caracterização molecular por PFGE. Todas as amostras VRE carreavam o gene vanA. Entre os E. faecalis vancomicina-resistentes, dois distintos grupos clonais foram observados. E. faecium resistente a vancomicina pertencentes a cinco clones distintos foram demonstrados por tipagem molecular. Todos esses clones foram diferentes do primeiro clone de enterococo resistente a vancomicina isolado oito anos atrás em nosso hospital

Novel downstream process and analytical tools developed for Influenza VLP vaccine

Vaccination remains the most effective way to prevent the infection with Influenza viruses. However, their constant antigenic drift implies that current human Influenza vaccines need to be annually updated with high inherent costs. Virus-like particles (VLPs) have become widely used as vaccine candidates because of their versatility, immunogenicity, and safety profile. In this iBET project we are attempting to produce a candidate for a universal vaccine for which 35 different VLPs (mono, trivalent and pentavalent) were purified. Here we describe three recent advances on Influenza VLPs bioprocessing: two new analytical tools and the development of an integrated all filtration purification process, inserted in the “anything but chromatography” concept. The first method is a label-free tool that uses Biolayer interferometry technology applied on an Octet platform to quantify Influenza VLPs at all stages of DSP. Human and avian sialic acid receptors were used, in order to quantify hemagglutinin (HA) content in several mono- and multivalent Influenza VLP strains. The applied method was able to detect and quantify HA from crude sample up to final VLP product with high throughput, real-time results and improved detection limits, when compared to traditional approaches, crucial for in-line monitoring of DSP. Using a click-chemistry approach that involves Azidohomoalanine incorporation and functionalization, Influenza VLPs were selectively and fluorescently tagged. Taking into account that this chemical tag does not affect particle size, charge and biological activity we report here a valuable tool to online/at-line product monitoring during DSP optimization of virus related biopharmaceuticals. Moreover, using this tool coupled with FACS we were able to discriminate between VLPs and baculovirus, the major impurity of the system. The proposed all-filtration process will be described, with special focus on the clarification stage, followed by multiple ultrafiltration and diafiltration steps to achieve the needed concentration and purity specifications. Using this all-filtration platform, we are able to speed up the time process, to improve the scale-up and to reduce costs due to the removal of chromatographic steps