Mining for Social Serendipity

A common social problem at an event in which people do not personally know all of the other participants is the natural tendency for cliques to form and for discussions to mainly happen between people who already know each other. This limits the possibility for people to make interesting new acquaintances and acts as a retarding force in the creation of new links in the social web. Encouraging users to socialize with people they don't know by revealing to them hidden surprising links could help to improve the diversity of interactions at an event. The goal of this paper is to propose a method for detecting "surprising" relationships between people attending an event. By "surprising" relationship we mean those relationships that are not known a priori, and that imply shared information not directly related with the local context of the event (location, interests, contacts) at which the meeting takes place. To demonstrate and test our concept we used the Flickr community. We focused on a community of users associated with a social event (a computer science conference) and represented in Flickr by means of a photo pool devoted to the event. We use Flickr metadata (tags) to mine for user similarity not related to the context of the event, as represented in the corresponding Flickr group. For example, we look for two group members who have been in the same highly specific place (identified by means of geo-tagged photos), but are not friends of each other and share no other common interests or, social neighborhood

Somatic complaints in frontotemporal dementia.

Frontotemporal dementia (FTD) is associated with a broad spectrum of clinical characteristics. The objective of this study was to analyze the prevalence of unexplained somatic complaints in neuropathologically verified FTD. We also examined whether the somatic presentations correlated with protein pathology or regional brain pathology and if the patients with these somatic features showed more depressive traits. Ninety-seven consecutively neuropathologically verified FTLD patients were selected. All 97 patients were part of a longitudinal study of FTD and all medical records were systematically reviewed. The somatic complaints focused on were headache, musculoskeletal, gastro/urogenital and abnormal pain response. Symptoms of somatic character (either somatic complaints and/or abnormal pain response) were found in 40.2%. These patients did not differ from the total group with regard to gender, age at onset or duration. Six patients showed exaggerated reactions to sensory stimuli, whereas three patients showed reduced response to pain. Depressive traits were present in 38% and did not correlate with somatic complaints. Suicidal behavior was present in 17 patients, in 10 of these suicidal behavior was concurrent with somatic complaints. No clear correlation between somatic complaints and brain protein pathology, regional pathology or asymmetric hemispherical atrophy was found. Our results show that many FTD patients suffer from unexplained somatic complaints before and/or during dementia where no clear correlation can be found with protein pathology or regional degeneration. Somatic complaints are not covered by current diagnostic criteria for FTD, but need to be considered in diagnostics and care. The need for prospective studies with neuropathological follow up must be stressed as these phenomena remain unexplained, misinterpreted, bizarre and, in many cases, excruciating

Original Article Somatic complaints in frontotemporal dementia

Abstract: Frontotemporal dementia (FTD) is associated with a broad spectrum of clinical characteristics. The objective of this study was to analyze the prevalence of unexplained somatic complaints in neuropathologically verified FTD. We also examined whether the somatic presentations correlated with protein pathology or regional brain pathology and if the patients with these somatic features showed more depressive traits. Ninety-seven consecutively neuropathologically verified FTLD patients were selected. All 97 patients were part of a longitudinal study of FTD and all medical records were systematically reviewed. The somatic complaints focused on were headache, musculoskeletal, gastro/urogenital and abnormal pain response. Symptoms of somatic character (either somatic complaints and/or abnormal pain response) were found in 40.2%. These patients did not differ from the total group with regard to gender, age at onset or duration. Six patients showed exaggerated reactions to sensory stimuli, whereas three patients showed reduced response to pain. Depressive traits were present in 38% and did not correlate with somatic complaints. Suicidal behavior was present in 17 patients, in 10 of these suicidal behavior was concurrent with somatic complaints. No clear correlation between somatic complaints and brain protein pathology, regional pathology or asymmetric hemispherical atrophy was found. Our results show that many FTD patients suffer from unexplained somatic complaints before and/or during dementia where no clear correlation can be found with protein pathology or regional degeneration. Somatic complaints are not covered by current diagnostic criteria for FTD, but need to be considered in diagnostics and care. The need for prospective studies with neuropathological follow up must be stressed as these phenomena remain unexplained, misinterpreted, bizarre and, in many cases, excruciating

Cerebrospinal fluid neurofilament light chain protein levels in subtypes of frontotemporal dementia

Background: Frontotemporal dementia (FTD) is recognised as a clinically and morphologically heterogeneous group of interrelated neurodegenerative conditions. One of the subtypes within this disease spectrum is the behavioural variant FTD (bvFTD). This is known to be a varied disorder with a mixture of tau-positive and tau-negative underlying pathologies. The other subtypes include semantic dementia (SD), which generally exhibits tau-negative pathology, and progressive non-fluent aphasia (PNFA), which is usually tau-positive. As the clinical presentation of these subtypes may overlap, a specific diagnosis can be difficult to attain and today no specific biomarker can predict the underlying pathology. Neurofilament light chain protein (NFL), a cytoskeletal constituent of intermediate filaments, is thought to reflect neuronal and axonal death when appearing in the cerebrospinal fluid (CSF). NFL has been shown to be elevated in CSF in patients with FTD compared with AD and controls. Our hypothesis was that the levels of NFL also differ between the subtypes of FTD and may indicate the underlying pathological subtype. Methods: We retrospectively analysed data from previous CSF analyses in 34 FTD cases (23 bvFTD, seven SD, four PNFA), 20 AD cases, and 26 healthy controls. A separate group of 10 neuropathologically verified and subtyped FTD cases (seven tau-negative, three tau-positive) were also analysed. Result: NFL levels were significantly higher in FTD compared with both AD (p<0.001) and controls (p<0.001). The NFL levels of SD and bvFTD were significantly higher (p<0.001) compared with AD. The biomarker profiles of PNFA and AD were similar. In the neuropathologically verified FTD cases, NFL was higher in the tau-negative than in the tau-positive cases (exact p=0.017). Conclusions: The marked NFL elevation in some but not all FTD cases is likely to reflect the different underlying pathologies. The highest NFL values found in the SD group as well as in the neuropathologically verified tau-negative cases may be of subtype diagnostic value, if corroborated in larger patient cohorts. In bvFTD, a mixture of tau-positive and tau-negative underlying pathologies could possibly explain the intermediate NFL values