Dark-field digital holographic microscopy for 3D-tracking of gold nanoparticles

We present a new technique that combines off-axis Digital Holography and Dark Field Microscopy to track 100nm gold particles diffusing in water. We show that a single hologram is sufficient to localize several particles in a thick sample with a localization accuracy independent of the particle position. From our measurements we reconstruct the trajectories of the particles and derive their 3D diffusion coefficient. Our results pave the way for quantitative studies of the motion of single nanoparticle in complex media

No evidence for association between tau gene haplotypic variants and susceptibility to Creutzfeldt-Jakob disease

Contains fulltext : 52965.pdf ( ) (Open Access)BACKGROUND: A polymorphism at codon 129 of the prion protein gene (PRNP) is the only well-known genetic risk factor for Creutzfeldt-Jakob disease (CJD). However, there is increasing evidence that other loci outside the PRNP open reading frame might play a role in CJD aetiology as well. METHODS: We studied tau protein gene (MAPT) haplotypic variations in a population of sporadic and variant CJD patients. We tested 6 MAPT haplotype tagging SNPs (htSNPs) in a Dutch population-based sample of sporadic CJD (sCJD) patients and a cognitively normal control group of similar age distribution. We genotyped the same polymorphisms in two other sample groups of sCJD cases from Italy and the UK. In addition, we compared MAPT haplotypes between sCJD and variant CJD (vCJD) patients. RESULTS: Single locus and haplotype analyses did not detect any significant difference between sCJD cases and controls. When we compared MAPT haplotypes between sCJD and variant CJD (vCJD) patients, we found that two of them were represented differently (H1f: 8% in sCJD versus 2% in vCJD; H1j:1% in sCJD versus 7% in vCJD). However, these two haplotypes were rare in both groups of patients, and taking the small sample sizes into account, we cannot exclude that the differences are due to chance. None of the p-values remained statistically significant after applying a multiple testing correction. CONCLUSION: Our study shows no evidence for an association between MAPT gene variations and sCJD, and some weak evidence for an association to vCJD

Role of MAPT mutations and haplotype in frontotemporal lobar degeneration in Northern Finland

<p>Abstract</p> <p>Background</p> <p>Frontotemporal lobar degeneration (FTLD) consists of a clinically and neuropathologically heterogeneous group of syndromes affecting the frontal and temporal lobes of the brain. Mutations in microtubule-associated protein tau (<it>MAPT</it>), progranulin (<it>PGRN</it>) and charged multi-vesicular body protein 2B (<it>CHMP2B</it>) are associated with familial forms of the disease. The prevalence of these mutations varies between populations. The H1 haplotype of <it>MAPT </it>has been found to be closely associated with tauopathies and with sporadic FTLD. Our aim was to investigate <it>MAPT </it>mutations and haplotype frequencies in a clinical series of patients with FTLD in Northern Finland.</p> <p>Methods</p> <p><it>MAPT </it>exons 1, 2 and 9–13 were sequenced in 59 patients with FTLD, and <it>MAPT </it>haplotypes were analysed in these patients, 122 patients with early onset Alzheimer's disease (eoAD) and 198 healthy controls.</p> <p>Results</p> <p>No pathogenic mutations were found. The H2 allele frequency was 11.0% (<it>P </it>= 0.028) in the FTLD patients, 9.8% (<it>P </it>= 0.029) in the eoAD patients and 5.3% in the controls. The H2 allele was especially clustered in patients with a positive family history (<it>P </it>= 0.011) but did not lower the age at onset of the disease. The ApoE4 allele frequency was significantly increased in the patients with eoAD and in those with FTLD.</p> <p>Conclusion</p> <p>We conclude that although pathogenic <it>MAPT </it>mutations are rare in Northern Finland, the <it>MAPT </it>H2 allele may be associated with increased risks of FTLD and eoAD in the Finnish population.</p

Frequency of the C9orf72 hexanucleotide repeat expansion in patients with amyotrophic lateral sclerosis and frontotemporal dementia: a cross-sectional study.

We aimed to accurately estimate the frequency of a hexanucleotide repeat expansion in C9orf72 that has been associated with a large proportion of cases of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD)

MOUVEMENTS DE VIBRATIONS ETUDIES PAR HOLOGRAPHIE HETERODYNE

International audienceEn jouant avec l'amplitude, la phase et la fréquence des deux bras référence et signal, l'holographie hétérodyne est bien adaptée à l'analyse des vibrations. Les bandes latérales de vibrations peuvent être visualiées et des mesures stroboscopiques, sensibles à la phase mécanique peuvent être faites

Epidemiology of systemic sclerosis and systemic sclerosis-associated interstitial lung disease

Aurore Bergamasco,1 Nadine Hartmann,2 Laura Wallace,3 Patrice Verpillat41YolaRx Consultants, Paris, France; 2Boehringer Ingelheim International GmbH, Ingelheim am Rhein, Germany; 3Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CO, USA; 4Boehringer Ingelheim Pharma GmbH &amp; Co. KG, Ingelheim am Rhein, GermanyBackground: Interstitial lung disease (ILD) is one of the leading causes of mortality in patients with systemic sclerosis (SSc). To further understand this patient population, we present the first systematic review on the epidemiology of SSc and SSc-associated ILD (SSc-ILD).Methods: Bibliographic databases and web sources were searched for studies including patients with SSc and SSc-ILD in Europe and North America (United States and Canada). The systematic review was limited to publications in English, German, French, Spanish, Italian, and Portuguese, published between January 1, 2000 and February 29, 2016. For all publications included in the review, the methodologic quality was assessed. For each dimension and region, data availability in terms of quantity and consistency of reported findings was evaluated.Results: Fifty publications reporting epidemiologic data (prevalence, incidence, demographic profile, and survival and mortality) were included; 39 included patients with SSc and 16 included patients with SSc-ILD. The reported prevalence of SSc was 7.2&ndash;33.9 and 13.5&ndash;44.3 per 100,000 individuals in Europe and North America, respectively. Annual incidence estimates were 0.6&ndash;2.3 and 1.4&ndash;5.6 per 100,000 individuals in Europe and North America, respectively. Associated ILD was present in &sim;35% of the patients in Europe and &sim;52% of the patients in North America. In Europe, a study estimated the prevalence and annual incidence of SSc-ILD at 1.7&ndash;4.2 and 0.1&ndash;0.4 per 100,000 individuals, respectively. In both Europe and North America, SSc-ILD was diagnosed at a slightly older age than SSc, with both presentations of the disease affecting 2&ndash;3 times more women than men. Ten-year survival in patients with SSc was reported at 65&ndash;73% in Europe and 54&ndash;82% in North America, with cardiorespiratory manifestations (including ILD) associated with poor prognosis.Conclusion: This systematic review confirms that SSc and SSc-ILD are rare, with geographic variation in prevalence and incidence.Keywords: epidemiology, interstitial lung disease, systemic sclerosi