Neural correlates of timbre change in harmonic sounds

Timbre is a major structuring force in music and one of the most important and ecologically relevant features of auditory events. We used sound stimuli selected on the basis of previous psychophysiological studies to investigate the neural correlates of timbre perception. Our results indicate that both the left and right hemispheres are involved in timbre processing, challenging the conventional notion that the elementary attributes of musical perception are predominantly lateralized to the right hemisphere. Significant timbre-related brain activation was found in well-defined regions of posterior Heschl's gyrus and superior temporal sulcus, extending into the circular insular sulcus. Although the extent of activation was not significantly different between left and right hemispheres, temporal lobe activations were significantly posterior in the left, compared to the right, hemisphere, suggesting a functional asymmetry in their respective contributions to timbre processing. The implications of our findings for music processing in particular and auditory processing in general are discussed.

Performance of the ImmunoCard STAT! E. coli O157:H7 test for detection of Escherichia coli O157:H7 in stools

ImmunoCard STAT! E. coli O157:H7 (Meridian Diagnostics, Inc., Cincinnati, Ohio) is a novel rapid (10-min) test for the presence of Escherichia coli O157:H7 in stools. The test may be performed either directly on stool specimens or on an overnight broth culture of stool. In a multicenter prospective study, 14 of 14 specimens positive by culture for E. coli O157:H7 were positive by the ImmunoCard STAT! O157:H7 test, and there were no false positives from 263 culture-negative specimens. In a retrospective study, the test was positive in 339 (81%) of 417 stored culture-positive specimens and the specificity was 95% (98 of 103 specimens). No false positives were associated with alternate stool pathogens. The ImmunoCard STAT! O157:H7 test has high sensitivity and specificity.

Isolated meningeal vasculopathy associated with Clostridium septicum infection

A 28-year-old patient with acute lymphoblastic leukemia and neutropenia developed necrotizing enterocolitis and Clostridium septicum bacteremia, followed by rhabdomyolysis, skin rash, and acute neurologic changes. Numerous cortical leptomeningeal enhancements were present on head MRI. Meningeal and brain biopsy showed segmental, full-thickness lysis of smooth muscle cells of medium-sized meningeal vessels with overall preservation of the structure of the vessel wall.

[Anticaries effectiveness of D(+)-galactose]

The influence of different galactose concentrations on the cariogenic effect of Streptococcus mutans (strains: DSM 20381 and DSM 20523) in a sucrose diet (33%) was examined in an animal experiment. The treated Wistar rats were free of pathogenic germs at the beginning of the experiment. The experimental conditions were approximately in accordance with the "Consensus statement" of the American Dental Association. The sides of the teeth, the amount of film, the abrasion of the chewing surfaces, the amount of surface and fissure caries and the animals general condition were evaluated. The anticaries effectiveness of galactose is dependent on its concentration: 5.0% galactose reduces the amount of caries on a high significance level, lowers the abrasion of the chewing surfaces, possibly because of the increased amount of serum calcium related to this galactose concentration, and diminishes the amount of film. 1.5% galactose prevents caries significantly and strongly reduces the amount of film; 0.5% galactose reduces the amount of caries non-significantly, but diminishes the amount of film. The effect is based on the property of galactose to occupy the receptors of the pellicle (layer of glycoprotein on the tooth enamel), hence the adherence of specific germs (for example, Streptococcus mutans) ceases in whole or in part.