806 research outputs found
The mental health system in Brazil: Policies and future challenges
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
A multidisciplinary treatment of congenitally missing maxillary lateral incisors: a 14-year follow-up case report
Absence of the maxillary lateral incisor creates an aesthetic problem which can be managed in various ways. The condition requires careful treatment planning and consideration of the options and outcomes following either space closure or prosthetic replacement. Recent developments in restorative dentistry have warranted a re-evaluation of the approach to this clinical situation. Factors relating both to the patient and the teeth, including the presentation of malocclusion and the effect on the occlusion must be considered. The objective of this study was to describe the etiology, prevalence and alternative treatment modalities for dental agenesis and to present a clinical case of agenesis of the maxillary lateral incisors treated by the closure of excessive spaces and canine re-anatomization. A clinical case is presented to illustrate the interdisciplinary approach between orthodontics and restorative dentistry for improved esthetic results. In this report, the treatment of a girl with a Class II malocclusion of molars and canines with missing maxillary lateral incisors and convex facial profile is shown. Treatment was successfully achieved and included the space closure of the areas corresponding to the missing upper lateral incisors, through movement of the canines and the posterior teeth to mesial by fixed appliances as well as the canines transformation in the maxillary lateral incisors. This is a 14-year follow-up case report involving orthodontics and restorative dentistry in which pretreatment, posttreatment, and long-term follow-up records for the patient are presented
Quantum physics in inertial and gravitational fields
Covariant generalizations of well-known wave equations predict the existence
of inertial-gravitational effects for a variety of quantum systems that range
from Bose-Einstein condensates to particles in accelerators. Additional effects
arise in models that incorporate Born reciprocity principle and the notion of a
maximal acceleration. Some specific examples are discussed in detail.Comment: 25 pages,1 figure,to appear in "Relativity in Rotating Frame
Tunable kinetic proofreading in a model with molecular frustration
In complex systems, feedback loops can build intricate emergent phenomena, so
that a description of the whole system cannot be easily derived from the
properties of the individual parts. Here we propose that inter-molecular
frustration mechanisms can provide non trivial feedback loops which can develop
nontrivial specificity amplification. We show that this mechanism can be seen
as a more general form of a kinetic proofreading mechanism, with an interesting
new property, namely the ability to tune the specificity amplification by
changing the reactants concentrations. This contrasts with the classical
kinetic proofreading mechanism in which specificity is a function of only the
reaction rate constants involved in a chemical pathway. These results are also
interesting because they show that a wide class of frustration models exists
that share the same underlining kinetic proofreading mechanisms, with even
richer properties. These models can find applications in different areas such
as evolutionary biology, immunology and biochemistry
Alternative Oxidase Mediates Pathogen Resistance in Paracoccidioides brasiliensis Infection
Thermally dimorphic pathogenic fungi are responsible for potentially life-threatening diseases of immunocompetent and immunocompromised individuals. These microorganisms grow as conidia-producing mycelia in the environment, which when inhaled by the host convert to the pathogenic yeast form at 37°C. During adaptation and growth, fungi interact with host immune cells and must cope with defense mechanisms such as imposed-oxidative stress (e.g., reactive oxygen species; ROS). Alternative oxidase (AOX) is an enzyme recently implicated in the reduction of ROS production by the mitochondria when triggered by external stimuli, such as temperature and ROS. During this work we have evaluated the relevance of AOX during infection with Paracoccidioides brasiliensis, the etiological agent of one of the most prevalent mycoses in Latin America, paracoccidioidomycosis. We show that PbAOX gene expression is stimulated after interaction with alveolar macrophages or in the presence of H2O2 and is essential for survival against fungicidal activity of both the immune cells and the ROS compound. Moreover, decreasing PbAOX gene expression in P. brasiliensis led to increased survival of infected mice. Altogether, our data supports a relevant role for AOX in the virulence of P. brasiliensis
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