Comparison of electroencephalographic spectra from normal children to spectra from children with reading and general academic problems

Comparison of electroencephalographic spectra from normal children to spectra from children with reading and general academic problem

An underwater vision compendium for the optometrist

A comprehensive compendium was assembled to aid the optometrist in understanding vision underwater and the unique visual needs of the SCUBA diver. Most every aspect of vision is altered underwater and a description of perceptual, optical, and physiolotical alterations is provided in the text. Partial adaptation to visual distortions gradually occurs as a function of time underwater, but adaptation can be accelerated with selected eye-hand activities. Methods of restoring the air-cornea interface are evaluated, and although the dive mask results in compromised visual function, it is still the most practical and cost effective means of restoring the refractive power of the eye. Based on personal experience and previous research, the authors suggest priorities for the novice diver selecting a dive mask. The ametropic diver is faced with choosing from four popularly available methods in selecting an underwater correction. Advantages and limitations of each method are cited. Lens bonded to the dive mask is the most versatile system but ultimate choice is dependent upon the diver\u27s specific, individual needs. In an appendix the authors explore a theoretical lens system that compensates for magnification created by the air-water interface of the facemask

Comparison of electroencephalographic spectra from normal children to spectra from children with reading and general academic problems

INTRODUCTION: Reading problems affect a significant proportion of children. Causes range from attention deficit disorders to disruption of information processing. Attempts have been made to classify reading disorders into diagnostic categories such as dyslexia, but these classifications have been unsatisfactory for a number of reasons. In this project, an attempt was made to classify children with reading difficulties based upon their electroencephalographic (EEG) spectra. SUBJECTS: Sixty-four subjects participated in this project; all were students in grades 3 through 8 at local schools. On the basis of standardized academic test results, 33 subjects were classified as normal (no score below the 40th percentile), 14 were classified as having an isolated reading problem (a score below the 40th percentile on reading and/or language, and scores above the 40th percentile on math and/or general ability), and 17 were classified as having general problems (a score below the 40th percentile on reading and/or language, and a score below the 40th percentile on math and/or general ability). METHODS: EEG spectra were recorded from electrode sites OZ, PZ, and CZ during the fifth minute of five tasks : sitting quietly, listening to story, reading a story, performing mental arithmetic, and copy forms. Spectra were divided into theta, alpha, and beta bands. RESULTS: Amplitudes of the EEG bands were compared for the three subject groups. No statistically significant differences between the groups were found. Several individual subjects had spectra suggestive of attention deficit disorder. CONCLUSIONS: Analysis of EEG spectra did not provide a useful means for differentiating the three groups of subjects used in this study. It is possible that recording at different electrode sites or using different stimulus conditions might have allowed better differentiation of the subject groups

Increased [H-3] quisqualic acid binding density in the dorsal striatum and anterior insula of alcoholics : A post-mortem whole-hemisphere autoradiography study

The function of group I metabotropic glutamate receptors mGluR1 and mGluR5 is involved in the hyperglutamatergic state caused by chronic alcohol. Preclinical studies suggest that group I mGluR modulation could serve as a novel treatment of alcoholism. Considering the wide role of glutamatergic neurochemistry in addiction, group I mGluR binding was studied in brain areas involved in decision-making, learning and memory. Post-mortem whole hemisphere autoradiography was used to study the binding density of [H-3] quisqualic acid, a potent group I mGluR agonist, in 9 Cloninger type 1 alcoholics, 8 Cloninger type 2 alcoholics and 10 controls. Binding was studied in the dorsal striatum, hippocampus and cortex. Alcoholics displayed a trend towards increased [ H-3] quisqualic acid binding in all brain areas. The most robust findings were in the putamen (p = 0.006) and anterior insula (p = 0.005), where both alcoholic subtypes displayed increased binding compared to the controls. These findings suggest altered group I mGluR function in alcoholic subjects in the dorsal striatum, which is involved in habitual learning, and in the anterior insula, which has a pivotal role in the perception of bodily sensations. Increased [H-3] quisqualic acid binding might suggest a beneficial impact of mGluR1/5 modulators in the treatment of alcoholism.Peer reviewe

The effect of illumination on the time to, and pupil area of, maximum mydriasis

This study was designed to evaluate the mydriatic effects of patients being dilated under differing illumination conditions. Twenty subjects, 1 a females and 1 a males, had their pupils dilated under darkened conditions and under normal illumination to determine if there would be a difference in the rate of mydriasis or overall pupil size at the point of maximum dilation. Iris colour and gender were separately evaluated factors in dilation results. Subjects were dilated using one drop each of 1% tetracaine, 2.5% phenylephrine HCI and 1% tropicamide. Pupil diameter was periodically measured using a Cogan pupillometer starting 6 minutes after drop instillation. Measurements with the pupillometer were taken at two-minute intervals throughout the 3 a-minute test period. The final measurement 33 minutes after instillation of the dilating drops was taken with a biomicroscope reticule; both horizontal and vertical diameters were measured. No Significant differences were seen between gender, iris colour and illumination type on the rate of maximum mydriasis. However, the relative pupil area was significantly greater following dilation under normal illumination conditions

Pathogenicity of sucrose-negative Yersinia strains found in pig tonsils

The aim of this work was to study the pathogenicity of sucrose-negative Yersinia strains isolated from pig tonsils with phenotypic and genotypic methods. All Yersinia pseudotuberculosis and 5 out of 8 of the sucrose-negative Y. enterocolitica strains were pathogenic. Three sucrose-negative Yersinia enterocolitica strains carried the ail gene and were pyrazinamidase negative showing that they were potentially pathogenic and may have lost the virulence plasmid during isolation and storage. Pyrazinamidase test was not reliable to predict the pathogenicity of Y. pseudotuberculosis strains. Using the PCR assays targeting the inv, ail and yadA genes sucrose-negative Yersinia strains could be differentiated from each other

Yersinia spp. in Wild Rodents and Shrews in Finland

Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small mammals as a reservoir of enteropathogenic Yersinia spp. is still obscure. In this study, the presence of Yersinia spp. was examined from 1840 wild small mammals, including voles, mice, and shrews, trapped in Finland during a 7-year period. We isolated seven Yersinia species. Y. enterocolitica was the most common species, isolated from 8% of the animals; while most of these isolates represented nonpathogenic biotype 1A, human pathogenic bioserotype 2/O:9 was also isolated from a field vole. Y. pseudotuberculosis of bioserotype 1/O:2 was isolated from two shrews. The ail gene, which is typically only found in the isolates of biotypes 1B and 2-5 associated with yersiniosis, was frequently (23%) detected in the nonpathogenic isolates of biotype 1A and sporadically (6%) in Yersinia kristensenii isolates. Our results suggest that wild small mammals, especially voles, may serve as carriers for ail-positive Y. enterocolitica 1A and Y. kristensenii. We also demonstrate that voles and shrews sporadically excrete pYV-positive Y. enterocolitica 2/O:9 and Y. pseudotuberculosis 1/O:2, respectively, in their feces and, thus, can serve as a contamination source for vegetables by contaminating the soil.Peer reviewe