Local vs. long-range infection in unidimensional epidemics

We study the effects of local and distance interactions in the unidimensional contact process (CP). In the model, each site of a lattice is occupied by an individual, which can be healthy or infected. As in the standard CP, each infected individual spreads the disease to one of its first-neighbors with rate $\lambda$, and with unitary rate, it becomes healthy. However, in our model, an infected individual can transmit the disease to an individual at a distance $\ell$ apart. This step mimics a vector-mediated transmission. We observe the host-host interactions do not alter the critical exponents significantly in comparison to a process with only L\'evy-type interactions. Our results confirm, numerically, early field-theoretic predictions.Comment: 8 pages, 6 figures, to appear on Frontiers in Physic

O Relacionamento Entre Instituições de Ensino Superior e Seus Estudantes a Partir de Ambientes Virtuais de Aprendizagem

O ambiente no qual estão inseridas as instituições de ensino superior (IES) tornou-se competitivo. As estratégias de marketing, especialmente as com foco no relacionamento, têm apresentado diferenças para a captação e retenção de alunos em cursos de graduação. Os estudos em Ambientes Virtuais de Aprendizagem (AVAs), como mais uma ferramenta de relacionamento entre as IES e seus alunos torna-se importantes. O objetivo deste estudo é, portanto, identificar os fatores considerados relevantes nos AVAs para facilitar a construção de um relacionamento mais duradouro entre as IES e seus alunos. Esta pesquisa descritiva, com método quantitativo, realizou-se com 241 alunos dos cursos de graduação em administração de duas IES, do último semestre, uma de Joinville, SC e outra de Blumenau, SC. Pressupõe-se que estes alunos do ultimo ano têm mais experiência com os AVAs, e tiveram mais tempo para desenvolver um relacionamento de mais duradouro com estas instituições. O instrumento de coleta de dados foi um questionário estruturado, com questões predominantemente fechadas e a adoção do escalograma de Likert. Entre as características mais importantes e valorizadas pelos alunos estão as notas das disciplinas; conteúdos das disciplinas e materiais de aulas; contato com professores (emails/mensagens); serviços de matrícula e pagamentos on-line; e acesso à biblioteca

Local vs. Long-Range Infection in Unidimensional Epidemics

We study the effects of local and distance interactions in the unidimensional contact process (CP). In the model, each site of a lattice is occupied by an individual, which can be healthy or infected. As in the standard CP, each infected individual spreads the disease to one of its first-neighbors with rate λ, and with unitary rate, it becomes healthy. However, in our model, an infected individual can transmit the disease to an individual at a distance ℓ apart. This step mimics a vector-mediated transmission. We observe the host-host interactions do not alter the critical exponents significantly in comparison to a process with only Lévy-type interactions. Our results confirm, numerically, early field-theoretic predictions

In vitro maturation impacts cumulus–oocyte complex metabolism and stress in cattle

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOThe influence of in vitro maturation (IVM) in oocytes is still not totally understood. The aim of this study was to determine the influence of IVM on the metabolism and homeostasis of bovine cumulus-oocyte complexes. In the present study, we demonstrated1546881893FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2014/21034-32014/03281-32014/22887-02013/08135-22012/50533-2306978/2014-8The authors would like to thank the staff and students at the LMMD, Marcos Chiaratti, Gustavo Duarte, Marcel Nakashima, Hélio Alves Martins Júnior, José Luis Paz Jara, Patricia Kubo Fontes and Augusto de Castro Netto for their assistance with the sample

The Leishmania amazonensis TRF (TTAGGG repeat-binding factor) homologue binds and co-localizes with telomeres

<p>Abstract</p> <p>Background</p> <p>Telomeres are specialized structures at the end of chromosomes essential for maintaining genome stability and cell viability. The importance of telomeric proteins for telomere maintenance has increased our interest in the identification of homologues within the genus <it>Leishmania</it>. The mammalian TRF1 and TRF2 proteins, for example, bind double-stranded telomeres via a Myb-like DNA-binding domain and are involved with telomere length regulation and chromosome end protection. In addition, TRF2 can modulate the activity of several enzymes and influence the conformation of telomeric DNA. In this work, we identified and characterized a <it>Leishmania </it>protein (LaTRF) homologous to both mammalian TRF1 and TRF2.</p> <p>Results</p> <p>LaTRF was cloned using a PCR-based strategy. ClustalW and bl2seq sequence analysis showed that LaTRF shared sequence identity with the <it>Trypanosoma brucei </it>TRF (TbTRF) protein and had the same degree of sequence similarities with the dimerization (TRFH) and the canonical DNA-binding Myb-like domains of both mammalian TRFs. LaTRF was predicted to be an 82.5 kDa protein, indicating that it is double the size of the trypanosome TRF homologues. Western blot and indirect immunofluorescence combined with fluorescence <it>in situ </it>hybridization showed that LaTRF, similarly to hTRF2, is a nuclear protein that also associates with parasite telomeres. Native and full length LaTRF and a mutant bearing the putative Myb-like domain expressed in bacteria bound double-stranded telomeric DNA <it>in vitro</it>. Chromatin immunoprecipitation showed that LaTRF interacted specifically with telomeres <it>in vivo</it>.</p> <p>Conclusion</p> <p>The nuclear localization of LaTRF, its association and co-localization with parasite telomeres and its high identity with TbTRF protein, support the hypothesis that LaTRF is a <it>Leishmania </it>telomeric protein.</p

Analysis of binding properties and specificity through identification of the interface forming residues (IFR) for serine proteases in silico docked to different inhibitors

<p>Abstract</p> <p>Background</p> <p>Enzymes belonging to the same super family of proteins in general operate on variety of substrates and are inhibited by wide selection of inhibitors. In this work our main objective was to expand the scope of studies that consider only the catalytic and binding pocket amino acids while analyzing enzyme specificity and instead, include a wider category which we have named the Interface Forming Residues (IFR). We were motivated to identify those amino acids with decreased accessibility to solvent after docking of different types of inhibitors to sub classes of serine proteases and then create a table (matrix) of all amino acid positions at the interface as well as their respective occupancies. Our goal is to establish a platform for analysis of the relationship between IFR characteristics and binding properties/specificity for bi-molecular complexes.</p> <p>Results</p> <p>We propose a novel method for describing binding properties and delineating serine proteases specificity by compiling an exhaustive table of interface forming residues (IFR) for serine proteases and their inhibitors. Currently, the Protein Data Bank (PDB) does not contain all the data that our analysis would require. Therefore, an <it>in silico </it>approach was designed for building corresponding complexes</p> <p>The IFRs are obtained by "rigid body docking" among 70 structurally aligned, sequence wise non-redundant, serine protease structures with 3 inhibitors: bovine pancreatic trypsin inhibitor (BPTI), ecotine and ovomucoid third domain inhibitor. The table (matrix) of all amino acid positions at the interface and their respective occupancy is created. We also developed a new computational protocol for predicting IFRs for those complexes which were not deciphered experimentally so far, achieving accuracy of at least 0.97.</p> <p>Conclusions</p> <p>The serine proteases interfaces prefer polar (including glycine) residues (with some exceptions). Charged residues were found to be uniquely prevalent at the interfaces between the "miscellaneous-virus" subfamily and the three inhibitors. This prompts speculation about how important this difference in IFR characteristics is for maintaining virulence of those organisms.</p> <p>Our work here provides a unique tool for both structure/function relationship analysis as well as a compilation of indicators detailing how the specificity of various serine proteases may have been achieved and/or could be altered. It also indicates that the interface forming residues which also determine specificity of serine protease subfamily can not be presented in a canonical way but rather as a matrix of alternative populations of amino acids occupying variety of IFR positions.</p

Identification and characterization of Tc1/mariner-like DNA transposons in genomes of the pathogenic fungi of the Paracoccidioides species complex

<p>Abstract</p> <p>Background</p> <p><it>Paracoccidioides brasiliensis </it>(Eukaryota, Fungi, Ascomycota) is a thermodimorphic fungus, the etiological agent of paracoccidioidomycosis, the most important systemic mycoses in Latin America. Three isolates corresponding to distinct phylogenetic lineages of the <it>Paracoccidioides </it>species complex had their genomes sequenced. In this study the identification and characterization of class II transposable elements in the genomes of these fungi was carried out.</p> <p>Results</p> <p>A genomic survey for DNA transposons in the sequence assemblies of <it>Paracoccidioides</it>, a genus recently proposed to encompass species <it>P. brasiliensis </it>(harboring phylogenetic lineages S1, PS2, PS3) and <it>P. lutzii </it>(<it>Pb01-like </it>isolates), has been completed. Eight new <it>Tc1/mariner </it>families, referred to as Trem (<b>Tr</b>ansposable <b>e</b>lement <b>m</b>ariner), labeled A through H were identified. Elements from each family have 65-80% sequence similarity with other <it>Tc1/mariner </it>elements. They are flanked by 2-bp TA target site duplications and different termini. Encoded DDD-transposases, some of which have complete ORFs, indicated that they could be functionally active. The distribution of Trem elements varied between the genomic sequences characterized as belonging to <it>P. brasiliensis </it>(S1 and PS2) and <it>P. lutzii</it>. TremC and H elements would have been present in a hypothetical ancestor common to <it>P. brasiliensis </it>and <it>P. lutzii</it>, while TremA, B and F elements were either acquired by <it>P. brasiliensis </it>or lost by <it>P. lutzii </it>after speciation. Although TremD and TremE share about 70% similarity, they are specific to <it>P. brasiliensis </it>and <it>P. lutzii</it>, respectively. This suggests that these elements could either have been present in a hypothetical common ancestor and have evolved divergently after the split between <it>P. brasiliensis </it>and <it>P. Lutzii</it>, or have been independently acquired by horizontal transfer.</p> <p>Conclusions</p> <p>New families of <it>Tc1/mariner </it>DNA transposons in the genomic assemblies of the <it>Paracoccidioides </it>species complex are described. Families were distinguished based on significant BLAST identities between transposases and/or TIRs. The expansion of Trem in a putative ancestor common to the species <it>P. brasiliensis </it>and <it>P. lutzii </it>would have given origin to TremC and TremH, while other elements could have been acquired or lost after speciation had occurred. The results may contribute to our understanding of the organization and architecture of genomes in the genus <it>Paracoccidioides</it>.</p

Fractional Exhaled Nitric Oxide Measurements and Screening of Obstructive Sleep Apnea in a Sleep-Laboratory Setting: A Cross-Sectional Study

PURPOSE: Obstructive sleep apnea (OSA) is a common condition characterized by repetitive collapse of the upper airways and intermittent oxygen desaturation, which may lead to airway inflammation. Here, we explored whether fractional exhaled nitric oxide (FeNO) levels provide a non-invasive screening tool of OSA. METHODS: Over a 3-month period, FeNO levels were measured in consecutive non-smoking patients referred for a sleep laboratory. All patients underwent full polysomnography. OSA severity was classified based on the apnea/hypopnea index: ≥ 5.0/h as any OSA, ≥ 15.0/h as moderate/severe OSA, and ≥ 30.0/h as severe OSA. FeNO was measured by a portable device (NIOX-MINO®; Aerocrine AB, Solna, Sweden) and expressed as parts per billion (ppb). Discrimination by area under the curve (AUC) and binary logistic regression were performed. RESULTS: A total of 229 subjects were evaluated. Mean FeNO values were similar among subjects without OSA or with OSA: 16.9 ± 10.6 ppb versus 20.2 ± 14.5 ppb, p = 0.221; respectively. FeNO was not an inclusionary parameter to predict any OSA, moderate/severe OSA, and severe OSA: odds ratio (OR) 1.023 (95% confidence interval [CI]: 0.986-1.062); OR 1.012 (95% CI: 0.991-1.034); and OR 0.999 (95% CI: 0.980-1.018), respectively. The AUC values for FeNO in the diagnosis of any OSA, moderate/severe OSA, and severe OSA showed no discriminatory properties: AUC: 0.567 (95% CI: 0.464-0.670), AUC: 0.541 (95% CI: 0.465-0.618), and AUC: 0.535 (95% CI: 0.459-0.610); respectively. CONCLUSIONS: In a sleep-lab setting, our findings suggest that FeNO measurements are inconsequential in the screening of OSA in adults.info:eu-repo/semantics/publishedVersio