Missing levels in acoustic resonators

It is shown that the deviations of the experimental statistics of six chaotic acoustic resonators from Wigner-Dyson random matrix theory predictions are explained by a recent model of random missing levels. In these resonatorsa made of aluminum plates a the larger deviations occur in the spectral rigidity (SRs) while the nearest-neighbor distributions (NNDs) are still close to the Wigner surmise. Good fits to the experimental NNDs and SRs are obtained by adjusting only one parameter, which is the fraction of remaining levels of the complete spectra. For two Sinai stadiums, one Sinai stadium without planar symmetry, two triangles, and a sixth of the three-leaf clover shapes, was found that 7%, 4%, 7%, and 2%, respectively, of eigenfrequencies were not detected.

Microduplication of the ICR2 Domain at Chromosome 11p15 and Familial Silver-Russell Syndrome

Silver-Russell syndrome (SRS) is characterized by severe intrauterine and postnatal growth retardation in association with a typical small triangular face and other variable features. Genetic and epigenetic disturbances are detected in about 50% of the patients. Most frequently, SRS is caused by altered gene expression on chromosome 11p15 due to hypomethylation of the telomeric imprinting center (ICR1) that is present in at least 40% of the patients. Maternally inherited duplications encompassing ICR1 and ICR2 domains at 11p15 were found in a few patients, and a microduplication restricted to ICR2 was described in a single SRS child. We report on a microduplication of the ICR2 domain encompassing the KCNQ1, KCNQ1OT1, and CDKN1C genes in a three-generation family: there were four instances of paternal transmissions of the microduplication from a single male uniformly resulting in normal offspring, and five maternal transmissions, via two clinically normal sisters, with all the children exhibiting SRS. This report provides confirmatory evidence that a microduplication restricted to the ICR2 domain results in SRS when maternally transmitted. (C) 2011 Wiley-Liss, Inc.

Schilbach-Rott/blepharofacioskeletal syndrome in a Brazilian patient

We report on a 4-year-old girl with blepharophimosis, a typical facial gestalt and skeletal abnormalities seen in the blepharofacioskeletal syndrome (BFSS). A comparative review with previous cases provides further evidence that BFSS and Schilbach-Rott syndrome (SRS) are the same condition. (C) 2008 Wiley-Liss, Inc.

Effects of voluntary running on spatial memory and mature brain-derived neurotrophic factor expression in mice hippocampus after status epilepticus

Voluntary physical activity improves memory and learning ability in rodents, whereas status epilepticus has been associated with memory impairment. Physical activity and seizures have been associated with enhanced hippocampal expression of BDNF, indicating that this protein may have a dual role in epilepsy. The influence of voluntary physical activity on memory and BDNF expression has been poorly studied in experimental models of epilepsy. In this paper, we have investigated the effect of voluntary physical activity on memory and BDNF expression in mice with pilocarpine-incluced epilepsy. Male Swiss mice were assigned to four experimental groups: pilocarpine sedentary (PS), pilocarpine runners (PRs), saline sedentary (SS) and saline runners (SRs). Two days after pilocarpine-induced status epilepticus, the affected mice (PR) and their running controls (SR) were housed with access to a running wheel for 28 days. After that, the spatial memory and the expression of the precursor and mature forms of hippocampal BDNF were assessed. PR mice performed better than PS mice in the water maze test. In addition, PR mice had a higher amount of mature BDNF (14 kDa) relative to the total BDNF (14 kDa + 28 kDa + 32 kDa forms) content when compared with PS mice. These results show that voluntary physical activity improved the spatial memory and increased the hippocampal content of mature BDNF of mice with pilocarpine-induced status epilepticus. (C) 2009 Elsevier B.V. All rights reserved.