Cytometric analysis, genetic manipulation and antibiotic selection of the snail embryonic cell line Bge from Biomphalaria glabrata, the intermediate host of Schistosoma mansoni.

The invertebrate cell line, Bge, from embryos of the snail Biomphalaria glabrata, remains to date the only established cell line from any species of the Phylum Mollusca. Since its establishment in 1976 by Eder Hansen, few studies have focused on profiling its cytometrics, growth characteristics or sensitivity to xenobiotics. Bge cells are reputed to be challenging to propagate and maintain. Therefore, even though this cell line is a noteworthy resource, it has not been studied widely. With growing interest in functional genomics, including genetic transformation, to elucidate molecular aspects of the snail intermediate hosts responsible for transmission of schistosomiasis, and aiming to enhance the convenience of maintenance of this molluscan cell line, we deployed the xCELLigene real time approach to study Bge cells. Doubling times for three isolates of Bge, termed CB, SL and UK, were longer than for mammalian cell lines - longer than 40 h in complete Bge medium supplemented with 7% fetal bovine serum at 25 °C, ranging from ∼42 h to ∼157 h when 40,000 cells were seeded. To assess the potential of the cells for genetic transformation, antibiotic selection was explored. Bge cells were sensitive to the aminonucleoside antibiotic puromycin (from Streptomyces alboniger) from 5 μg/ml to 200 ng/ml, displaying a half maximal inhibitory concentration (IC50) of ∼1.91 μg/ml. Sensitivity to puromycin, and a relatively quick kill time (<48 h in 5 μg/ml) facilitated use of this antibiotic, together with the cognate resistance gene (puromycin N-acetyl-transferase) for selection of Bge cells transformed with the PAC gene (puroR). Bge cells transfected with a plasmid encoding puroR were partially rescued when cultured in the presence of 5 μg/ml of puromycin. These findings pave the way for the development of functional genomic tools applied to the host-parasite interaction during schistosomiasis and neglected tropical trematodiases at large

Gravitational diffraction radiation

We show that if the visible universe is a membrane embedded in a higher-dimensional space, particles in uniform motion radiate gravitational waves because of spacetime lumpiness. This phenomenon is analogous to the electromagnetic diffraction radiation of a charge moving near to a metallic grating. In the gravitational case, the role of the metallic grating is played by the inhomogeneities of the extra-dimensional space, such as a hidden brane. We derive a general formula for gravitational diffraction radiation and apply it to a higher-dimensional scenario with flat compact extra dimensions. Gravitational diffraction radiation may carry away a significant portion of the particle's initial energy. This allows to set stringent limits on the scale of brane perturbations. Physical effects of gravitational diffraction radiation are briefly discussed.Comment: 5 pages, 2 figures, RevTeX4. v2: References added. Version to appear in Phys. Rev.

Atividade Física e Exercício Físico: Especificidades no Doente Cardíaco

A atividade física é atualmente um comportamento de grande importância para a promoção de um estilo de vida saudável, contudo vários estudos têm demonstrado elevada prevalência de inatividade e comportamentos sedentários nas pessoas com doença cardiovascular. Uma prática regular de atividade física e de exercício físico em níveis adequados assegura diversos benefícios para a pessoa com doença cardiovascular. Programas de reabilitação cardíaca e de prevenção secundária têm como um dos principais objetivos o incentivo à adoção de estilos de vida mais ativos. Neste artigo de revisão, os conceitos e recomendações sobre a atividade física e o exercício físico estruturado em pessoas com doença cardiovascular, vão ser abordados

Extracellular enolase of Candida albicans is involved in colonization of mammalian intestinal epithelium

Enolase is secreted by C. albicans and is present in its biofilms although its extracellular function is unknown. Here we show that extracellular enolase mediates the colonization of small intestine mucosa by C. albicans. Assays using intestinal mucosa disks show that C. albicans adhesion is inhibited, in a dose dependent mode, either by pretreatment of intestinal epithelium mucosa disks with recombinant C. albicans enolase (70% at 0.5 mg/ml enolase) or by pretreatment of C. albicans yeasts with anti-enolase antibodies (48% with 20 µg antiserum). Also using flow cytometry, immunoblots of conditioned media and confocal microscopy we demonstrate that enolase is present in biofilms and that the extracellular enolase is not an artifact due to cell lysis, but must represent functional secretion of a stable form. This is the first direct evidence that C. albicans extracellular enolase mediates colonization on its primary translocation site. Also, because enolase is encoded by a single locus in C. albicans, its dual role peptide, as glycolytic enzyme and extracellular peptide, is a remarkable example of gene sharing in fungi

Mensuração dos custos e avaliação de rendas em sistemas de produção de leite caprino nos Cariris Paraibanos.

Resumo: Objetivou-se mensurar o custo de produção do leite e avaliar a renda na atividade caprina por sistemas de produção. Os sistemas de produção estão localizados na microrregião dos Cariris Paraibanos e foram definidos por critérios de eficiência técnica e econômica, com método de agrupamento por análise multivariada e formação de cinco grupos. O método utilizado para o custo de produção foi o custo operacional, e o critério adotado para a conversão do custo da atividade leiteira para o custo do leite foi da participação da renda do leite na renda bruta da atividade. Os critérios adotados de análise de rendas foram margem bruta e margem líquida. No cômputo do custo de produção do leite de cabra, os valores foram de R$0,67/L; R$ 0,73/L; R$0,80/L; R$ 0,88/L; e R$1,21/L para os sistemas de produção 1, 2, 3, 4 e 5. Os sistemas de produção 1 e 2, de alta tecnologia, com margem líquida de R$ 9.147,30 e R$3.995,18 na atividade leiteira, foram os que apresentaram os menores custos e economicamente são os mais vantajosos. [Calculation of the costs and evaluation of incomes in different systems of production of goat milk in Cariris Paraibanos]. Abstract: The study aimed at calculating milk production cost and evaluating the income in goat milk farm activity by production systems. The production systems are located in the sub region of Cariris Paraibanos and they were defined by criteria of technical and economical efficiency, with grouping method by multivariate data analysis and formation of five groups. The method used for production cost was the operational cost, and the criterion adopted for the conversion of the milk activity cost for the cost of the milk was the participation of the milk income in the gross income of the activity. The criteria adopted for analysis of income were gross margin and net margin. In the count of goat milk production cost the values were R$ 0.67/L R$0.73/L, R$ 0.80/L, R$0.88/L and R$ 1.21/L for the production systems 1, 2, 3, 4 and 5. Systems of production 1 and 2 with high technology and net margin of R$9,147.30 and R$ 3,995.18 in the milk activity, were the ones that showed the lowest costs and they are economically the most advantageou

A combined approach for comparative exoproteome analysis of Corynebacterium pseudotuberculosis

Background: Bacterial exported proteins represent key components of the host-pathogen interplay. Hence, we sought to implement a combined approach for characterizing the entire exoproteome of the pathogenic bacterium Corynebacterium pseudotuberculosis, the etiological agent of caseous lymphadenitis (CLA) in sheep and goats. Results: An optimized protocol of three-phase partitioning (TPP) was used to obtain the C. pseudotuberculosis exoproteins, and a newly introduced method of data-independent MS acquisition (LC-MSE) was employed for protein identification and label-free quantification. Additionally, the recently developed tool SurfG+ was used for in silico prediction of sub-cellular localization of the identified proteins. In total, 93 different extracellular proteins of C. pseudotuberculosis were identified with high confidence by this strategy; 44 proteins were commonly identified in two different strains, isolated from distinct hosts, then composing a core C. pseudotuberculosis exoproteome. Analysis with the SurfG+ tool showed that more than 75% (70/93) of the identified proteins could be predicted as containing signals for active exportation. Moreover, evidence could be found for probable non-classical export of most of the remaining proteins. Conclusions: Comparative analyses of the exoproteomes of two C. pseudotuberculosis strains, in addition to comparison with other experimentally determined corynebacterial exoproteomes, were helpful to gain novel insights into the contribution of the exported proteins in the virulence of this bacterium. The results presented here compose the most comprehensive coverage of the exoproteome of a corynebacterial species so far