Clustering and spatial correlations of the neuronal cytoplasmic inclusions, astrocytic plaques and ballooned neurons in corticobasal degeneration

This study tested three hypotheses: (1) that there is clustering of the neuronal cytoplasmic inclusions (NCI), astrocytic plaques (AP) and ballooned neurons (BN) in corticobasal degeneration (CBD), (2) that the clusters of NCI and BN are not spatially correlated, and (3) that the lesions are correlated with disease ‘stage’. In 50% of the regions, clusters of lesions were 400–800 µm in diameter and regularly distributed parallel to the tissue boundary. Clusters of NCI and BN were larger in laminae II/III and V/VI, respectively. In a third of regions, the clusters of BN and NCI were negatively spatially correlated. Cluster size of the BN in the parahippocampal gyrus (PHG) was positively correlated with disease ‘stage’. The data suggest the following: (1) degeneration of the cortico-cortical pathways in CBD, (2) clusters of NCI and BN may affect different anatomical pathways and (3) BN may develop after the NCI in the PHG.

The spatial patterns of pathological brain lesions in 12 patients with corticobasal degeneration

Corticobasal degeneration (CBD) is a rare and progressive neurological disorder characterised by the presence of ballooned neurons (BN) and tau positive inclusions in neurons and glial cells. We studied the spatial patterns of the BN, tau positive neurons with inclusions (tau + neurons), and tau positive plaques in the neocortex and hippocampus in 12 cases of CBD. All lesions were aggregated into clusters and in many brain areas, the clusters were distributed in a regular pattern parallel to the tissue boundary. In the majority of cortical areas, the clusters of BN were larger in the lower compared with the upper laminae while the clusters of tau + neurons were larger in the upper laminae. Clusters of BN and tau + neurons were either negatively correlated or not significantly correlated in the upper and lower cortical laminae. Hence, BN and tau + lesions in CBD exhibit similar spatial patterns as lesions in Alzheimer's disease (AD), dementia with Lewy bodies (DLB) and Pick's disease (PD). The location, sizes and distribution of the clusters in the neocortex suggest that the tau + lesions may be associated with the degeneration of the feedforward and the BN the feedback cortico-cortical and/or the efferent cortical pathways. © 2001 Elsevier Science Ireland Ltd. All rights reserved.

Clustering of cerebral cortical lesions in patients with corticobasal degeneration

Clustering of ballooned neurons (BN) and tau positive neurons with inclusion bodies (tau+ neurons) was studied in the upper and lower laminae of the frontal, parietal and temporal cortex in 12 patients with corticobasal degeneration (CBD). In a significant proportion of brain areas examined, BN and tau+ neurons exhibited clustering with a regular distribution of clusters parallel to the pia mater. A regular pattern of clustering of BN and tau+ neurons was observed equally frequently in all cortical areas examined and in the upper and lower laminae. No significant correlations were observed between the cluster sizes of BN or tau+ neurons in the upper compared with the lower cortex or between the cluster sizes of BN and tau+ neurons. The results suggest that BN and tau+ neurons in CBD exhibit the same type of spatial pattern as lesions in Alzheimer's disease, Lewy body dementia and Pick's disease. The regular periodicity of the cerebral cortical lesions is consistent with the degeneration of the cortico-cortical projections in CBD.

Laminar distribution of ballooned neurons and tau positive neurons with inclusions in patients with corticobasal degeneration

The laminar distribution of ballooned neurons (BN) and tau positive neurons with inclusions (tau+ neurons) was studied in the frontal and temporal cortex in twelve patients with corticobasal degeneration (CBD). In the majority of brain areas, the density of BN and tau+ neurons was maximal in the lower and upper cortical laminae respectively. The densities of tau+ neurons in the upper and lower cortex were positively correlated. In the majority of brain areas, however, no correlations were observed between the densities of BN and tau+ neurons. The laminar distribution of the BN may reflect the degeneration of the feedback cortico-cortical and/or the efferent cortical pathways. By contrast, the distribution of the tau+ neurons may reflect the degeneration of the feed-forward cortico-cortical pathways. In addition, BN and tau+ neurons may arise as a result of distinct pathological processes.

Dynamics of Boolean networks: an exact solution

The dynamics of Boolean networks (BN) with quenched disorder and thermal noise is studied via the generating functional method. A general formulation, suitable for BN with any distribution of Boolean functions, is developed. It provides exact solutions and insight into the evolution of order parameters and properties of the stationary states, which are inaccessible via existing methodology. We identify cases where the commonly used annealed approximation is valid and others where it breaks down. Broader links between BN and general Boolean formulas are highlighted.

Multi-class subcellular location prediction for bacterial proteins

Two algorithms, based onBayesian Networks (BNs), for bacterial subcellular location prediction, are explored in this paper: one predicts all locations for Gram+ bacteria and the other all locations for Gram- bacteria. Methods were evaluated using different numbers of residues (from the N-terminal 10 residues to the whole sequence) and residue representation (amino acid-composition, percentage amino acid-composition or normalised amino acid-composition). The accuracy of the best resulting BN was compared to PSORTB. The accuracy of this multi-location BN was roughly comparable to PSORTB; the difference in predictions is low, often less than 2%. The BN method thus represents both an important new avenue of methodological development for subcellular location prediction and a potentially value new tool of true utilitarian value for candidate subunit vaccine selection.

Fiber-type transitions and satellite cell activation in low-frequency-stimulated muscles of young and aging rats

We examined satellite cell content and the activity of satellite cell progeny in tibialis anterior muscles of young (15 weeks) and aging (101 weeks) Brown Norway (BN) rats, after they were exposed for 50 days to a standardized and highly reproducible regime of chronic low-frequency electrical stimulation. Chronic low-frequency electrical stimulation was successful in inducing fast-to-slow fiber-type transformation, characterized by a 2.3-fold increase in the proportion of IIA fibers and fourfold and sevenfold decreases in the proportion of IID/X and IIB fibers in both young and aging BN rats. These changes were accompanied by a twofold increase in the satellite cell content in both the young and aging groups; satellite cell content reached a level that was significantly higher in the young group (p < .04). The total muscle precursor cell content (i.e., satellite cells plus progeny), however, did not differ between groups, because there was a greater number of satellite cell progeny passing through the proliferative and differentiative compartments of the aging group. The resulting 1.5-fold increase in myonuclear content was similar in the young and aging groups. We conclude that satellite cells and satellite cell progeny of aging BN rats possess an unaltered capacity to contribute to the adaptive response.

On an Extremal Problem concerning Bernstein Operators

* The second author is supported by the Alexander-von-Humboldt Foundation. He is on leave from: Institute of Mathematics, Academia Sinica, Beijing 100080, People’s Republic of China.

Sobolev-Morrey Type Inequality for Riesz Potentials, Associated with the Laplace-Bessel Differential Operator

2000 Mathematics Subject Classification: 42B20, 42B25, 42B35

Az általános szerződési feltételként a fogyasztói szerződés részévé váló választottbírósági kikötés tisztességtelenségéről

A választottbíráskodás történetileg elsősorban a kereskedelmi jogvitákra szabottan kialakított sajátos vitarendezési mód. Aligha meglepő hát, hogy a fogyasztói jogviták arbitrálhatóságának kérdése időről időre felmerül. Az utóbbi időben – figyelemmel az uniós jogi fejleményekre, valamint a magyar jogfejlődési tendenciákra is – különösen a fogyasztói szerződésekbe ÁSZF útján inkorporált választottbírósági kikötések jogi sorsa vet fel izgalmas kérdéseket. A jelen tanulmány ezek egy részét igyekszik körüljárni.

Middle school teachers' intentions to refer eating disorder students for professional counseling

Eating disorders can lead to a negative impact on students' academic growth, nutrition and can cause death (Claude-Pierre, 1997; Manley, Rickson, & Standeven, 2000; Romeo, 1996). Early intervention by referring students to professional counseling might help counter these negative consequences. The teacher is in the position to assist students by providing health information, identifying those with problems, and intervening for a variety of dysfunctions that may include the eating disorders called anorexia nervosa and bulimia nervosa (Myers-Clark & Christopher, 2000). However teachers are in a difficult position to know when to address student concerns and judge what action to take (Ransley, 1999). Teachers' engagement seems crucial (Smolak, Harris, Levine, & Shisslak, 2001) since eating disorders are being identified in younger children. The purpose of this study was to examine (a) the relationships of the theoretical constructs, attitude, subjective norm, and perceived behavioral control of the theory of planned behavior as predictors of behavioral intention (Ajzen & Fishbein, 1980) of middle school teachers to identify and refer suspected anorexia nervosa (AN) and/or bulimia nervosa (BN) students for professional help; and (b) the actual behavior of middle school teachers who reported having ever referred a student suspected of having AN and BN and those teachers who reported not having made such a referral. One hundred fourteen middle school teachers in Broward County, Florida volunteered to participate in the ex post facto research. Data were collected from a questionnaire. Multiple regression analysis revealed that the constructs of subjective norm (perception of what others think about one's performance of behavior combined with motivation to comply) and perceived behavioral control (perception regarding the extent of the difficulty of performing the behavior) were predictive of teachers' intent (likelihood of engaging in a behavior) to refer. However, the analysis revealed that attitude (overall positive or negative feeling with respect to performing the behavior) was not predictive of teachers' intent. Discriminant function analysis revealed that both intent and perceived behavioral control were predictive of group membership, either having referred a student suspected of having an eating disorder for counseling or not having made such a referral. Attitude and subjective norm were not predictive of group membership.

Dissolved Black Nitrogen (DBN) in Freshwater Environments

Biomass burning results in the formation and accumulation of pyrogenic products such as black carbon (BC) and black nitrogen (BN) in soils. The ubiquitous presence of pyrogenic products in natural dissolved organic matter (DOM) and potential implications in global carbon cycling have recently been reported. However, little is known about the environmental dynamics or the importance in the global N cycle of dissolved BN (DBN; or heteroaromatic N). Here we report the coupling between DBN and dissolved BC (DBC) in ultrafiltered DOM from six headwater streams across a climatic region of North America, suggesting similar combustion sources, and that DOC may play an important role in the translocation of soil BN to the dissolved phase. The export of potentially recalcitrant riverine DBN to the ocean may affect the biogeochemical cycling of N and possibly the microbial community structure in aquatic environments.

The impact of income and social status on population health: a scenario based simulation for nursing students

The development of critical thinking and communication skills is an essential part of Baccalaureate and Practical Nursing education. Scenario-based simulation, a form of experiential learning, directly engages students in the learning process. This teaching learning method has been shown to increase students’ understanding of the influence of their personal beliefs and values when working with clients and to improve therapeutic communication and critical thinking skills. Students in both the BN (Collaborative) and PN Programs at the Centre for Nursing Studies demonstrate a strong theoretical understanding of the impact of income and social status on population health but often experience difficulty applying this knowledge to the clinical situations involving clients and families. The purpose of the project was to develop a scenario-based simulation activity to provide nursing students with first-hand experiences of the impact of income and social status on health service accessibility. A literature review and stakeholder consultations were conducted to inform the project. The findings of these initiatives and Kolb’s Experiential Learning Theory were used to guide all aspects of the project. This report is an account of how the income and social status simulation and its accompanying materials were developed. This project provided an excellent learning opportunity that demonstrated the use of advanced nursing competencies.

La página de la mujer en Qué sucedió en siete días

Fil: Valobra, Adriana. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.