Spectral Domain Optical Coherence Tomography in Diffuse Unilateral Subacute Neuroretinitis

Purpose. To describe the SD-OCT findings in patients with diffuse unilateral subacute neuroretinitis (DUSN) and evaluate CRT and RNFL thickness. Methods. Patients with clinical diagnosis of DUSN who were submitted to SD-OCT were included in the study. Complete ophthalmologic examination and SD-OCT were performed. Cirrus scan strategy protocols used were 200 × 200 macular cube, optic nerve head cube, and HD-5 line raster. Results. Eight patients with DUSN were included. Mean RNFL thickness was 80.25 μm and 104.75 μm for affected and normal eyes, respectively. Late stage had mean RNFL thickness of 74.83 μm compared to 96.5 μm in early stage. Mean CMT was 205.5 μm for affected eyes and 255.13 μm for normal fellow eyes. Conclusion. RNFL and CMT were thinner in DUSN eyes compared to normal eyes. Late-stage disease had more pronounced thinning compared to early-stage patients. This thinning in RNFL and CMT may reflect the low visual acuity in patients with DUSN

Ciprofloxacin/amikacin combination therapy: evaluation in biofilms of Pseudomonas aeruginosa overproducting efflux pumps

International audienc

The determination of the apsidal angles and Bertrand's theorem

We derive an expression for the determination of the apsidal angles that holds good for arbitrary central potentials. Then we discuss under what conditions the apsidal angles remain independent of the mechanical energy and angular momentum in the central force problem. As a consequence, an alternative and non-perturbative proof of Bertrand's theorem is obtained.Comment: Latex file, one figure; submitted for publicatio

Biosurfactants as Multifunctional Remediation Agents of Environmental Pollutants Generated by the Petroleum Industry

Fuel and oil spills during the exploration, refining, and distribution of oil and petrochemicals are primarily responsible for the accumulation of organic pollutants in the environment. The reduction in contamination caused by hydrocarbons, heavy metals, oily effluents, and particulate matter generated by industrial activities and the efficient recovery of oil at great depths in an environmentally friendly way pose a challenge, as recovery and cleaning processes require the direct application of surface-active agents, detergents, degreasers, or solvents, often generating other environmental problems due to the toxicity and accumulation of these substances. Thus, the application of natural surface-active agents is an attractive solution. Due to their amphipathic structures, microbial surfactants solubilize oil through the formation of small aggregates (micelles) that disperse in water, with numerous applications in the petroleum industry. Biosurfactants have proven their usefulness in solubilizing oil trapped in rock, which is a prerequisite for enhanced oil recovery (EOR). Biosurfactants are also important biotechnological agents in anti-corrosion processes, preventing incrustations and the formation of biofilms on metallic surfaces, and are used in formulations of emulsifiers/demulsifiers, facilitate the transport of heavy oil through pipelines, and have other innovative applications in the oil industry. The use of natural surfactants can reduce the generation of pollutants from the use of synthetic detergents or chemical solvents without sacrificing economic gains for the oil industry. Therefore, investments in biotechnological processes are essential. It is predicted that, in the not-too-distant future, natural surfactants will become viable from an economic standpoint and dominate the world market. The application of biosurfactants in these settings would lead to industrial growth and environmental sustainability. The main goal of this paper is to provide an overview of diverse applications of biosurfactants on environmental remediation, petroleum biotechnology, and the oil industry through a scientific literature review

A secreted serine protease of Paracoccidioides brasiliensis and its interactions with fungal proteins

<p>Abstract</p> <p>Background</p> <p><it>Paracoccidioides brasiliensis </it>is a thermodimorphic fungus, the causative agent of paracoccidioidomycosis (PCM). Serine proteases are widely distributed and this class of peptidase has been related to pathogenesis and nitrogen starvation in pathogenic fungi.</p> <p>Results</p> <p>A cDNA (<it>Pb</it>sp) encoding a secreted serine protease (<it>Pb</it>SP), was isolated from a cDNA library constructed with RNAs of fungal yeast cells recovered from liver of infected mice. Recombinant <it>Pb</it>SP was produced in <it>Escherichia coli</it>, and used to develop polyclonal antibodies that were able to detect a 66 kDa protein in the <it>P. brasiliensis </it>proteome. <it>In vitro </it>deglycosylation assays with endoglycosidase H demonstrated that <it>Pb</it>SP is a <it>N</it>-glycosylated molecule. The <it>Pb</it>sp transcript and the protein were induced during nitrogen starvation. The <it>Pb</it>sp transcript was also induced in yeast cells infecting murine macrophages. Interactions of <it>Pb</it>SP with <it>P. brasiliensis </it>proteins were evaluated by two-hybrid assay in the yeast <it>Saccharomyces cerevisiae</it>. <it>Pb</it>SP interacts with a peptidyl prolyl cis-trans isomerase, calnexin, HSP70 and a cell wall protein PWP2.</p> <p>Conclusions</p> <p>A secreted subtilisin induced during nitrogen starvation was characterized indicating the possible role of this protein in the nitrogen acquisition. <it>Pb</it>SP interactions with other <it>P. brasiliensis </it>proteins were reported. Proteins interacting with <it>Pb</it>SP are related to folding process, protein trafficking and cytoskeleton reorganization.</p

Effects of descending positive end-expiratory pressure on lung mechanics and aeration in healthy anaesthetized piglets

INTRODUCTION: Atelectasis and distal airway closure are common clinical entities of general anaesthesia. These two phenomena are expected to reduce the ventilation of dependent lung regions and represent major causes of arterial oxygenation impairment in anaesthetic conditions. The behaviour of the elastance of the respiratory system (E(rs)), as well as the lung aeration assessed by computed tomography (CT) scan, was evaluated during a descendent positive end-expiratory pressure (PEEP) titration. This work sought to evaluate the potential usefulness of E(rs )monitoring to set the PEEP in order to prevent tidal recruitment and hyperinflation of healthy lungs under general anaesthesia. METHODS: PEEP titration (from 16 to 0 cmH(2)O, tidal volume of 8 ml/kg) was performed, and at each PEEP, CT scans were obtained during end-expiratory and end-inspiratory pauses in six healthy, anaesthetized and paralyzed piglets. The distribution of lung aeration was determined and the tidal re-aeration was calculated as the difference between end-expiratory and end-inspiratory poorly aerated and normally aerated areas. Similarly, tidal hyperinflation was obtained as the difference between end-inspiratory and end-expiratory hyperinflated areas. E(rs )was estimated from the equation of motion of the respiratory system during all PEEP titration with the least-squares method. RESULTS: Hyperinflated areas decreased from PEEP 16 to 0 cmH(2)O (ranges decreased from 24–62% to 1–7% at end-expiratory pauses and from 44–73% to 4–17% at end-inspiratory pauses) whereas normally aerated areas increased (from 30–66% to 72–83% at end-expiratory pauses and from 19–48% to 73–77% at end-inspiratory pauses). From 16 to 8 cmH(2)O, E(rs )decreased with a corresponding reduction in tidal hyperinflation. A flat minimum of E(rs )was observed from 8 to 4 cmH(2)O. For PEEP below 4 cmH(2)O, E(rs )increased in association with a rise in tidal re-aeration and a flat maximum of the normally aerated areas. CONCLUSION: In healthy piglets under a descending PEEP protocol, the PEEP at minimum E(rs )presented a compromise between maximizing normally aerated areas and minimizing tidal re-aeration and hyperinflation. High levels of PEEP, greater than 8 cmH(2)O, reduced tidal re-aeration but increased hyperinflation with a concomitant decrease in normally aerated areas

MHC class I stability is modulated by cell surface sialylation in human dendritic cells

PD/BD/52472/2014 project (Ref. 38870) POCI-01-0145-FEDER-007728Maturation of human Dendritic Cells (DCs) is characterized by increased expression of antigen presentation molecules, and overall decreased levels of sialic acid at cell surface. Here, we aimed to identify sialylated proteins at DC surface and comprehend their role and modulation. Mass spectrometry analysis of DC’s proteins, pulled down by a sialic acid binding lectin, identified molecules of the major human histocompatibility complex class I (MHC-I), known as human leucocyte antigen (HLA). After desialylation, DCs showed significantly higher reactivity with antibodies specific for properly folded MHC-I-β2-microglobulin complex and for β2-microglobulin but showed significant lower reactivity with an antibody specific for free MHC-I heavy chain. Similar results for antibody reactivities were observed for TAP2-deficient lymphoblastoid T2 cells, which express HLA-A*02:01. Using fluorescent peptide specifically fitting the groove of HLA-A*02:01, instead of antibody staining, also showed higher peptide binding on desialylated cells, confirming higher surface expression of MHC-I complex. A decay assay showed that desialylation doubled the half-life of MHC-I molecules at cell surface in both DCs and T2 cells. The biological impact of DC´s desialylation was evaluated in co-cultures with autologous T cells, showing higher number and earlier immunological synapses, and consequent significantly increased production of IFN-γ by T cells. In summary, sialic acid content modulates the expression and stability of complex MHC-I, which may account for the improved DC-T synapses.publishersversionpublishe

Activité de traitements par ciprofloxacine et/ou amikacine, en condition planctonique et en biofilm, vis-à-vis de souches de Pseudomonas aeruginosa surexprimant un efflux.

International audienc

The second International Symposium on Fungal Stress: ISFUS

The topic of ‘fungal stress’ is central to many important disciplines, including medical mycology, chronobiology, plant and insect pathology, industrial microbiology, material sciences, and astrobiology. The International Symposium on Fungal Stress (ISFUS) brought together researchers, who study fungal stress in a variety of fields. The second ISFUS was held in May 8-11 2017 in Goiania, Goiás, Brazil and hosted by the Instituto de Patologia Tropical e Saúde Pública at the Universidade Federal de Goiás. It was supported by grants from CAPES and FAPEG. Twenty-seven speakers from 15 countries presented their research related to fungal stress biology. The Symposium was divided into seven topics: 1. Fungal biology in extreme environments; 2. Stress mechanisms and responses in fungi: molecular biology, biochemistry, biophysics, and cellular biology; 3. Fungal photobiology in the context of stress; 4. Role of stress in fungal pathogenesis; 5. Fungal stress and bioremediation; 6. Fungal stress in agriculture and forestry; and 7. Fungal stress in industrial applications. This article provides an overview of the science presented and discussed at ISFUS-2017.Sao Paulo Research Foundation (FAPESP) 2010/06374-1, 2013/50518-6, 2014/01229-4Brazilian National Council for Scientific and Technological Development (CNPq) PQ2 302312/2011-0, PQ1D 308436/2014-8Coordenação de Aperfeiçoãmento de Pessoal de Nível Superior (CAPES) PAEP 88881.123209/2016-01Fundação de Amparo à Pesquisa do Estado de Goiás Brazil 20171026700011

Bisimilarity and refinement for hybrid(ised) logics

The complexity of modern software systems entails the need for reconfiguration mechanisms governing the dynamic evolution of their execution configurations in response to both external stimulus or internal performance measures. Formally, such systems may be represented by transition systems whose nodes correspond to the different configurations they may assume. Therefore, each node is endowed with, for example, an algebra, or a first-order structure, to precisely characterise the semantics of the services provided in the corresponding configuration. Hybrid logics, which add to the modal description of transition structures the ability to refer to specific states, offer a generic framework to approach the specification and design of this sort of systems. Therefore, the quest for suitable notions of equivalence and refinement between models of hybrid logic specifications becomes fundamental to any design discipline adopting this perspective. This paper contributes to this effort from a distinctive point of view: instead of focussing on a specific hybrid logic, the paper introduces notions of bisimilarity and refinement for hybridised logics, i.e. standard specification logics (e.g. propositional, equational, fuzzy, etc) to which modal and hybrid features were added in a systematic way.FC