Fast Automatic Segmentation of White Matter Streamlines Based on a Multi-Subject Bundle Atlas

This paper presents an algorithm for fast segmentation of white matter bundles from massive dMRI tractography datasets using a multisubject atlas. We use a distance metric to compare streamlines in a subject dataset to labeled centroids in the atlas, and label them using a per-bundle configurable threshold. In order to reduce segmentation time, the algorithm first preprocesses the data using a simplified distance metric to rapidly discard candidate streamlines in multiple stages, while guaranteeing that no false negatives are produced. The smaller set of remaining streamlines is then segmented using the original metric, thus eliminating any false positives from the preprocessing stage. As a result, a single-thread implementation of the algorithm can segment a dataset of almost 9 million streamlines in less than 6 minutes. Moreover, parallel versions of our algorithm for multicore processors and graphics processing units further reduce the segmentation time to less than 22 seconds and to 5 seconds, respectively. This performance enables the use of the algorithm in truly interactive applications for visualization, analysis, and segmentation of large white matter tractography datasets.     

The Robustness of the Early and Late Start Typology of Criminal Behaviour in Major Mental Disorder: A Conceptual Replication

The purpose of this study was to examine whether the early and late start typology of criminal behaviour in major mental disorder can be generalized to different populations than evaluated to date and is replicable in two different countries. A Dutch forensic sample (Sample 1) consisted of 260 reports to the court with early start offenders (n = 62) and late start offenders (n = 198). A Canadian civil psychiatric sample (Sample 2) consisted of file information collected from 78 involuntarily hospitalized civil psychiatric patients with an early start group (n = 38) and a late start group (n = 40). In both samples, early and late starters were compared on different domains. Results showed that in general, early starters have a higher risk of having problems in different domains. There were also differences in the early and late start typology between the Dutch and Canadian samples. Our results partially support the early and late starter typology within two different samples. This study showed that early starters typically have a higher risk of problems in different domains. This highlights the importance of different risk management and treatment strategies for both the early start and the late start group.     

Planning the restructuring of long-term care: The demand,need and provision of institutional long-term care beds in Newfoundland and Labrador

The Canadian population is aging. In Newfoundland and Labrador, nursing homes and supervised care facilities provide Long-Term Care (LTC). There may be a mismatch between the provision of LTC beds and clients' needs. To compare the type and annual rate of clients seeking placement, to LTC, incident annual cohorts (N = 1,496) in five provincial health regions within Newfoundland and Labrador were compared using objective measures of disability. Client need was assessed using a decision tree and the optimal distribution of LTC beds was determined.     

Case-control study of lymphoid neoplasm in three French areas: description, alcohol and tobacco consumption.

A multi-centre hospital-based case-control study was conducted in three regions of France between 2000 and 2003 in order to establish the risk factors of lymphoid neoplasms. We report here results concerning alcohol and tobacco consumption. A total of 298 cases and 276 controls, case-matched by inclusion centre, age and sex were included. Cases were classified according to the World Health Organization classification and validated by an expert panel of eight pathologists. Overall alcohol intake did not incur any risk increase for non-Hodgkin's lymphoma. Wine consumption marginally increased the risk of follicular lymphoma [odds ratio=2.19 (0.83-5.80)], with a higher risk for drinkers who started before the age of 20 years [odds ratio=4.04 (1.19-13.76)] and for drinkers who consumed more than 19 g of alcohol per day [odds ratio=4.37 (1.04-18.45)]. Beer and spirit consumption was not linked to non-Hodgkin's lymphoma risk. Tobacco consumption did not show a risk increase. The risk increase of follicular lymphoma due to wine consumption was new. We discuss this risk based on the French context, France being the European country with the highest alcohol consumption, particularly of wine.     

Three-dimensional mapping of hippocampal anatomy in unmedicated and lithium-treated patients with bipolar disorder.

Declarative memory impairments are common in patients with bipolar illness, suggesting underlying hippocampal pathology. However, hippocampal volume deficits are rarely observed in bipolar disorder. Here we used surface-based anatomic mapping to examine hippocampal anatomy in bipolar patients treated with lithium relative to matched control subjects and unmedicated patients with bipolar disorder. High-resolution brain magnetic resonance images were acquired from 33 patients with bipolar disorder (21 treated with lithium and 12 unmedicated), and 62 demographically matched healthy control subjects. Three-dimensional parametric mesh models were created from manual tracings of the hippocampal formation. Total hippocampal volume was significantly larger in lithium-treated bipolar patients compared with healthy controls (by 10.3%; p=0.001) and unmedicated bipolar patients (by 13.9%; p=0.003). Statistical mapping results, confirmed by permutation testing, revealed localized deficits in the right hippocampus, in regions corresponding primarily to cornu ammonis 1 subfields, in unmedicated bipolar patients, as compared to both normal controls (p=0.01), and in lithium-treated bipolar patients (p=0.03). These findings demonstrate the sensitivity of these anatomic mapping methods for detecting subtle alterations in hippocampal structure in bipolar disorder. The observed reduction in subregions of the hippocampus in unmedicated bipolar patients suggests a possible neural correlate for memory deficits frequently reported in this illness. Moreover, increased hippocampal volume in lithium-treated bipolar patients may reflect postulated neurotrophic effects of this agent, a possibility warranting further study in longitudinal investigations.     

The Relation between Work-related Psychosocial Factors and the Development of Depression

This review is based on a literature search made in January2007 on request by the Danish National Board of Industrial Injuries.The search in PubMed, EMBASE, and PsycINFO resulted in morethan 1,000 publications. This was reduced to 14 after the titles,abstracts, and papers were evaluated by using the followingcriteria: 1) a longitudinal study, 2) exposure to work-relatedpsychosocial factors, 3) the outcome a measure of depression,4) relevant statistical estimates, and 5) nonduplicated publication.Of the 14 studies, seven used standardized diagnostic instrumentsas measures of depression, whereas the other seven studies usedself-administered questionnaires. The authors found moderateevidence for a relation between the psychological demands ofthe job and the development of depression, with relative risksof approximately 2.0. However, indication of publication biasweakens the evidence. Social support at work was associatedwith a decrease in risk for future depression, as all four studiesdealing with this exposure showed associations with relativerisks of about 0.6. Even if this literature study has identifiedwork-related psychosocial factors that in high-quality epidemiologicstudies predict depression, studies are still needed that assessin more detail the duration and intensity of exposure necessaryfor developing depression. depression • prospective studies • psychology • work     

Ethanol potentiates dopamine uptake and increases cell surface distribution of dopamine transporters expressed in SK-N-SH and HEK-293 cells.

Ethanol increases dopaminergic release in the reward and reinforcement areas of the brain. The primary protein responsible for terminating dopamine (DA) neurotransmission is the plasma membrane-bound dopamine transporter (DAT). In vitro electrophysiological and biochemical studies in Xenopus laevis oocytes have previously shown ethanol potentiates DAT function and increases transporter-binding sites. The potentiating effect of ethanol on the transporter is eliminated in Xenopus oocytes by the DAT mutation glycine 130 to threonine. However, ethanol's action on DAT functional regulation has yet to be examined in mammalian cell expression systems. To further understand the molecular mechanisms of ethanol's action on DAT, we determined the direct mechanistic action of short-term (相似文献