Cellular and Behavioral Effects of Cranial Irradiation of the Subventricular Zone in Adult Mice

Background: In mammals, new neurons are added to the olfactory bulb (OB) throughout life. Most of these new neurons, granule and periglomerular cells originate from the subventricular zone (SVZ) lining the lateral ventricles and migrate via the rostral migratory stream toward the OB. Thousands of new neurons appear each day, but the function of this ongoing neurogenesis remains unclear. Methodology/Principal Findings: In this study, we irradiated adult mice to impair constitutive OB neurogenesis, and explored the functional impacts of this irradiation on the sense of smell. We found that focal irradiation of the SVZ greatly decreased the rate of production of new OB neurons, leaving other brain areas intact. This effect persisted for up to seven months after exposure to 15 Gray. Despite this robust impairment, the thresholds for detecting pure odorant molecules and short-term olfactory memory were not affected by irradiation. Similarly, the ability to distinguish between odorant molecules and the odorant-guided social behavior of irradiated mice were not affected by the decrease in the number of new neurons. Only long-term olfactory memory was found to be sensitive to SVZ irradiation. Conclusion/Significance: These findings suggest that the continuous production of adult-generated neurons is involved i

Quantum coherence in a dissipative-driven system and the optical Stern-Gerlach experiment

The quantum coherence of a single mode electromagnetic field in a cavity is analysed when a linear pumping is considered together with the damping mechanism of the cavity, An expression for the decoherence time of the field is estimated and it turns out to be independent of the pumping process, An interesting situation occurs in the long time limit when the action of the pumping is shown to induce a finite degree of quantum coherence in the stationary state of the field. For specific values of the parameters involved in the problem this state is very close to a coherent state and is considered in the realization of the optical Stem-Gerlach experiment. Other particular cases are also investigated.2214173214515

Minkowski structure for purity and entanglement of Gaussian bipartite states

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The relation between the symplectic and Lorentz groups is explored to investigate entanglement features in a two-mode bipartite Gaussian state. We verify that the correlation matrix of arbitrary Gaussian states can be associated with a hyperbolic space with a Minkowski metric, which is divided in two regions: separabilitylike and entanglementlike, in equivalence to timelike and spacelike in special relativity. This correspondence naturally allows the definition of two insightful invariant squared distance measures: one related to the purity and another related to amount of entanglement. The second distance allows us to define a measure for entanglement in terms of the invariant interval between the given state and its closest separable state, given in a natural manner without the requirement of a minimization procedure.885Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2009/16369-8

The Prostate Health Index Selectively Identifies Clinically Significant Prostate Cancer

Purpose: The Prostate Health Index (phi) is a new test combining total, free and [-2] proPSA into a single score. It was recently approved by the FDA and is now commercially available in the U.S., Europe and Australia. We investigate whether phi improves specificity for detecting clinically significant prostate cancer and can help reduce prostate cancer over diagnosis. Materials and Methods: From a multicenter prospective trial we identified 658 men age 50 years or older with prostate specific antigen 4 to 10 ng/ml and normal digital rectal examination who underwent prostate biopsy. In this population we compared the performance of prostate specific antigen, % free prostate specific antigen, [-2] proPSA and phi to predict biopsy results and, specifically, the presence of clinically significant prostate cancer using multiple criteria. Results: The Prostate Health Index was significantly higher in men with Gleason 7 or greater and "Epstein significant" cancer. On receiver operating characteristic analysis phi had the highest AUC for overall prostate cancer (AUCs phi 0.708, percent free prostate specific antigen 0.648, [-2] proPSA 0.550 and prostate specific antigen 0.516), Gleason 7 or greater (AUCs phi 0.707, percent free prostate specific antigen 0.661, [-2] proPSA 0.558, prostate specific antigen 0.551) and significant prostate cancer (AUCs phi 0.698, percent free prostate specific antigen 0.654, [-2] proPSA 0.550, prostate specific antigen 0.549). At the 90% sensitivity cut point for phi (a score less than 28.6) 30.1% of patients could have been spared an unnecessary biopsy for benign disease or insignificant prostate cancer compared to 21.7% using percent free prostate specific antigen. Conclusions: The new phi test outperforms its individual components of total, free and [-2] proPSA for the identification of clinically significant prostate cancer. Phi may be useful as part of a multivariable approach to reduce prostate biopsies and over diagnosis