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Benjamin Constant, Brazil

Amoedo N.D.,Federal University of Rio de Janeiro | Afonso A.O.,Federal University of Rio de Janeiro | Afonso A.O.,Catholic University of Petropolis | Cunha S.M.,Hospital Municipal Jesus | And 4 more authors.
PLoS ONE | Year: 2011

Objective: Increasing evidence has accumulated showing the role of APOBEC3G (A3G) and 3F (A3F) in the control of HIV-1 replication and disease progression in humans. However, very few studies have been conducted in HIV-infected children. Here, we analyzed the levels of A3G and A3F expression and induced G-to-A hypermutation in a group of children with distinct profiles of disease progression. Methodology/Principal Findings: Perinatally HIV-infected children were classified as progressors or long-term non-progressors according to criteria based on HIV viral load and CD4 T-cell counts over time. A group of uninfected control children were also enrolled in the study. PBMC proviral DNA was assessed for G-to-A hypermutation, whereas A3G and A3F mRNA were isolated and quantified through TaqMan® real-time PCR. No correlation was observed between disease progression and A3G/A3F expression or hypermutation levels. Although all children analyzed showed higher expression levels of A3G compared to A3F (an average fold of 5 times), a surprisingly high A3F-related hypermutation rate was evidenced in the cohort, irrespective of the child's disease progression profile. Conclusion: Our results contribute to the current controversy as to whether HIV disease progression is related to A3G/A3F enzymatic activity. To our knowledge, this is the first study analyzing A3G/F expression in HIV-infected children, and it may pave the way to a better understanding of the host factors governing HIV disease in the pediatric setting. © 2011 Amoêdo et al.

Goncalves R.V.,Federal University of Vicosa | Novaes R.D.,Federal University of Vicosa | Matta S.L.P.,Federal University of Vicosa | Benevides G.P.,Federal University of Ouro Preto | And 2 more authors.
Photomedicine and Laser Surgery | Year: 2010

Objective: The present study compared the effects of gallium-aluminum- arsenide diode laser and healing oil on fibroblasts, blood vessels, and collagen maturation of skin wounds in Wistar rats. Materials and Methods: Twenty-four male rats weighing 325 ± 27 g were used. Five wounds, 12 mm in diameter, were made on the animals' backs. The rats were randomly divided into four groups with six animals in each group. Control group: saline solution; L30 group: 30 J/cm 2 laser; L60 group: 60 J/cm 2 laser; Oil group: healing oil. Histomorphometric analysis was performed on the scar tissue removed from the different wounds every 4 d for 20 d. Results: On day 4, there were significantly more fibroblasts in the wounds treated with the laser and the healing oil compared to the controls. On day 8, there were significantly more fibroblasts in the oil group compared to the L30 and L60 groups. On the same day, the quantity of vessels was significantly greater in the L60 group compared to the other groups. On day 16, there was a significant increase in the number of blood vessels in the wounds treated with the 60 J/cm 2 laser compared to the other groups. Analysis of the collagen maturation index throughout the experiment showed significantly higher values in the L60 group compared to the other groups at all time points. Conclusion: The healing oil exerted a greater effect on fibroblast proliferation, whereas the 60 J/cm 2 laser was more effective in stimulating angiogenesis and scar-tissue maturation. © Copyright 2010, Mary Ann Liebert, Inc. 2010.

Santos R.A.M.,Laboratorio Nacional Of Computacao Cientifica | Portugal R.,Laboratorio Nacional Of Computacao Cientifica | Portugal R.,Catholic University of Petropolis | Boettcher S.,Emory University
Quantum Information Processing | Year: 2015

The properties of the coinless quantum-walk model have not been as thoroughly analyzed as those of the coined model. Both evolve in discrete time steps, but the former uses a smaller Hilbert space, which is spanned merely by the site basis. Besides, the evolution operator can be obtained using a process of lattice tessellation, which is very appealing. The moments of the probability distribution play an important role in the context of quantum walks. The ballistic behavior of the mean square displacement indicates that quantum-walk-based algorithms are faster than random-walk-based ones. In this paper, we obtain analytical expressions for the moments of the coinless model on d-dimensional lattices by employing the methods of Fourier transforms and generating functions. The mean square displacement for large times is explicitly calculated for the one- and two-dimensional lattices, and using optimization methods, the parameter values that give the largest spread are calculated and compared with the equivalent ones of the coined model. Although we have employed asymptotic methods, our approximations are accurate even for small numbers of time steps. © 2015, Springer Science+Business Media New York.

De Miranda E.C.,Catholic University of Petropolis | Pontes M.S.,Pontifical Catholic University of Rio de Janeiro | Da Silva Mello L.A.R.,Pontifical Catholic University of Rio de Janeiro
Proceedings of 6th European Conference on Antennas and Propagation, EuCAP 2012 | Year: 2012

In this work, results of the statistical estimation of the probability density function of fade slope in a 0.83μm free space optical communication system, operating across densely urbanised terrain, are presented and discussed. This system was installed linking the Engineering Buildings of University College and Imperial College, London and stayed in operation for 4 years. The statistical analysis of fade slope can provide insight into the dynamics of the fading phenomena as it represents the speed with which the attenuation grows and declines. © 2012 IEEE.

Baldisserotto M.,Catholic University of Petropolis | Fiori H.,Grande Rio University | Fiori R.,Grande Rio University | Ferrari L.H.R.,Grande Rio University | Mizerkowski M.D.,Grande Rio University
Radiologia Brasileira | Year: 2011

The literature reports only rare cases of urinary ascites, usually secondary to rupture of the bladder and not to renal calyx rupture. The present report describes an uncommon case of posterior urethral valve in a newborn with ascites caused by the rupture of a renal calyx that, to our knowledge, was diagnosed for the first time by ultrasonography.

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