Mapping hippocampal and ventricular change in Alzheimer disease

We developed an anatomical mapping technique to detect hippocampal and ventricular changes in Alzheimer disease (AD). The resulting maps are sensitive to longitudinal changes in brain structure as the disease progresses. An anatomical surface modeling approach was combined with surface-based statistics to visualize the region and rate of atrophy in serial MRI scans and isolate where these changes link with cognitive decline. Fifty-two high-resolution MRI scans were acquired from 12 AD patients (age: 68.4 +/- 1.9 years) and 14 matched controls (age: 71.4 +/- 0.9 years), each scanned twice (2.1 +/- 0.4 years apart). 3D parametric mesh models of the hippocampus and temporal horns were created in sequential scans and averaged across subjects to identify systematic patterns of atrophy. As an index of radial atrophy, 3D distance fields were generated relating each anatomical surface point to a medial curve threading down the medial axis of each structure. Hippocampal atrophic rates and ventricular expansion were assessed statistically using surface-based permutation testing and were faster in AD than in controls. Using color-coded maps and video sequences, these changes were visualized as they progressed anatomically over time. Additional maps localized regions where atrophic changes linked with cognitive decline. Temporal horn expansion maps were more sensitive to AD progression than maps of hippocampal atrophy, but both maps correlated with clinical deterioration. These quantitative, dynamic visualizations of hippocampal atrophy and ventricular expansion rates in aging and AD may provide a promising measure to track AD progression in drug trials. (C) 2004 Elsevier Inc. All rights reserved.

Political power, national identitiy and language

Afrikaans is the home language of 5.9 million people. During the 1980s, Afrikaans was the dominant state language and a widely-used lingua franca in South Africa and Namibia. But by the end of the twentieth century, English had replaced Afrikaans as the dominant state language and a decline in the use of Afrikaans was in evidence, even among native Afrikaans speakers. An examination of this language's twentieth-century journey helps illustrate the relationship(s) between political power, national identity, and the growth and/or decline of languages.

Morningness-eveningness orientation, optimal time-of-day and attitude change: Evidence for the systematic processing of a persuasive communication

This study investigates the effects of morningness-eveningness orientation and time-of-day on persuasion. In an attitude change paradigm, 120 female participants read a persuasive message that consisted of six counter-attitudinal arguments (anti-voluntary euthanasia) either in the morning (8:30 a.m.) or in the evening (7:00 p.m.). Attitude change was assessed by measuring attitudes towards the target issue before and after exposure to the message. Message processing was assessed by thought-listing and message recall tasks. Self-reported mood and arousal were monitored throughout. Participants were classified into M- and E-types according to their scores on the Horne and Ostberg (1976) MEQ questionnaire. When tested at their respective optimal time-of-day (i.e., morning for M-types/evening for E-types), M- and E-types reported higher energetic arousal, greater agreement with the message, greater message-congruent thinking, and a propensity for superior message recall compared to M- and E-types tested at their nonoptimal time-of-day (i.e., evening for M-types/morning for E-types). The attitude change in those tested at their optimal time-of-day was mediated by the level of message-congruent thinking. Results are interpreted in terms of the Elaboration Likelihood Model of persuasion. (c) 2005 Elsevier Ltd. All rights reserved.

Chronic smoking and alcoholism change expression of selective genes in the human prefrontal cortex

Background: Alcoholism is commonly associated with chronic smoking. A number of gene expression profiles of regions within the human mesocorticolimbic system have identified potential alcohol-sensitive genes; however, the influence of smoking on these changes was not taken into account. This study addressed the impact of alcohol and smoking on the expression of 4 genes, previously identified as alcoholism-sensitive. in the human prefrontal cortex (PFC). Methods: mRNA expression of apolipoprotein D, tissue inhibitor of the metalloproteinase 3, high-affinity glial glutamate transporter and midkine, was measured in the PFC of alcoholic Subjects and controls with and without smoking comorbidity using real-time polymerase chain reaction. Results: The results show that alcohol affects transcription of some of these genes. Additionally, smoking has a marked influence on gene expression. Conclusion: This study emphasizes the need for careful case selection in future gene expression studies to delineate the adaptive molecular process associated with smoking and alcohol.

Conceptual Frameworks for SIA Revisited: a cumulative effects study on lead contamination and economic change

This article trials three conceptual frameworks on an Australian case study of a small remote city suffering lead contamination, with cumulative effects from concurrent economic change due to downsizing in the mining industry. It interprets the usefulness of these frameworks, and explores two questions: can they apply to circumstances other than project assessment, and what are their relative merits as guides to SIA? All the frameworks reviewed can be used in non-project and cumulative SIA, although, if they had been used to predict the impacts in our case study, we may easily have been misled as to the resilience of the community. Choosing among these frameworks becomes a matter personal preference: each has different merits.