931 research outputs found
Nanomechanical IR spectroscopy for fast analysis of liquid-dispersed engineered nanomaterials
AbstractThe proliferated use of engineered nanomaterials (ENMs), e.g. in nanomedicine, calls for novel techniques allowing for fast and sensitive analysis of minute samples. Here we present nanomechanical IR spectroscopy (NAM-IR) for chemical analysis of picograms of ENMs. ENMs are nebulized directly from dispersion and efficiently collected on nanomechanical string resonators through a non-diffusion limited sampling method. Even very small amounts of sample can convert absorbed IR light into a measurable frequency detuning of the string through photothermal heating. An IR absorption spectrum is thus readily obtained by recording this detuning of the resonator over a range of IR wavelengths. Results recorded using NAM-IR agree well with corresponding results obtained through ATR-FTIR, and remarkably, measurement including sample preparation takes only a few minutes, compared to âŒ2 days sample preparation for ATR-FTIR. Resonator dimensions play an important role in NAM-IR, a relationship which will be elaborated here
Many obesity-associated SNPs strongly associate with DNA methylation changes at proximal promoters and enhancers
Background: The mechanisms by which genetic variants, such as single nucleotide polymorphisms (SNPs), identified in genome-wide association studies act to influence body mass remain unknown for most of these SNPs, which continue to puzzle the scientific community. Recent evidence points to the epigenetic and chromatin states of the genome as having important roles. Methods: We genotyped 355 healthy young individuals for 52 known obesity-associated SNPs and obtained DNA methylation levels in their blood using the Illumina 450 K BeadChip. Associations between alleles and methylation at proximal cytosine residues were tested using a linear model adjusted for age, sex, weight category, and a proxy for blood cell type counts. For replication in other tissues, we used two open-access datasets (skin fibroblasts, n = 62; four brain regions, n = 121-133) and an additional dataset in subcutaneous and visceral fat (n = 149). Results: We found that alleles at 28 of these obesity-associated SNPs associate with methylation levels at 107 proximal CpG sites. Out of 107 CpG sites, 38 are located in gene promoters, including genes strongly implicated in obesity (MIR148A, BDNF, PTPMT1, NR1H3, MGAT1, SCGB3A1, HOXC12, PMAIP1, PSIP1, RPS10-NUDT3, RPS10, SKOR1, MAP2K5, SIX5, AGRN, IMMP1L, ELP4, ITIH4, SEMA3G, POMC, ADCY3, SSPN, LGR4, TUFM, MIR4721, SULT1A1, SULT1A2, APOBR, CLN3, SPNS1, SH2B1, ATXN2L, and IL27). Interestingly, the associated SNPs are in known eQTLs for some of these genes. We also found that the 107 CpGs are enriched in enhancers in peripheral blood mononuclear cells. Finally, our results indicate that some of these associations are not blood-specific as we successfully replicated four associations in skin fibroblasts. Conclusions: Our results strongly suggest that many obesity-associated SNPs are associated with proximal gene regulation, which was reflected by association of obesity risk allele genotypes with differential DNA methylation. This study highlights the importance of DNA methylation and other chromatin marks as a way to understand the molecular basis of genetic variants associated with human diseases and traits
Modeling the actinides with disordered local moments
A first-principles disordered local moment (DLM) picture within the
local-spin-density and coherent potential approximations (LSDA+CPA) of the
actinides is presented. The parameter free theory gives an accurate description
of bond lengths and bulk modulus. The case of -Pu is studied in
particular and the calculated density of states is compared to data from
photo-electron spectroscopy. The relation between the DLM description, the
dynamical mean field approach and spin-polarized magnetically ordered modeling
is discussed.Comment: 6 pages, 4 figure
The burden of disease for children born alive with Turner syndromeâA European cohort study
BACKGROUND: Turner syndrome is a rare congenital anomaly caused by complete or partial X chromosome monosomy that may affect mortality and morbidity in childhood. METHODS: This population-based data-linkage cohort study, as part of the EUROlinkCAT project, investigated mortality and morbidity for the first 5âyears of life for liveborn European children diagnosed with Turner syndrome. Thirteen population-based registries in 10 countries from the European surveillance of congenital anomalies (EUROCAT) network participated. Data on children born 1995â2014 and diagnosed with Turner syndrome were linked to mortality, hospital and prescription records. Children with any congenital anomaly and children without a congenital anomaly were included for comparison on morbidity. RESULTS: Out of a population of 5.8 million livebirths 404 were diagnosed with Turner syndrome prenatally or in infancy and 95.5% survived to their fifth birthday. During the first year of life 72.3% (95% CI 59.5;81.6) of children with Turner syndrome were hospitalized, the median length of stay was 5.6âdays (95% CI 3.5;7.7) and 18.7% (95% CI 13.9;23.9) underwent surgery. After the first year of life hospitalizations and length of stay decreased but more children underwent surgery (30.8% [95% CI 17.6;44.7]). In the first 5âyears the percentage of children with Turner syndrome having a prescription for antibiotics was 12%â20% per year and increased with the age of child. CONCLUSIONS: In the first year of life, the burden of disease was relatively high for children with Turner syndrome. The outlook is more positive beyond the first year, though overall morbidity still exceeded that of children without congenital anomalies
Protocol for Work place adjusted Intelligent physical exercise reducing Musculoskeletal pain in Shoulder and neck (VIMS): a cluster randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>Neck and shoulder complaints are common among employees in sedentary occupations characterized by intensive computer use. Specific strength training is a promising type of physical exercise for relieving neck and shoulder pain in office workers. However, the optimal combination of frequency and exercise duration, as well as the importance of exercise supervision, is unknown. The VIMS study investigates in a cluster randomized controlled design the effectiveness of different time wise combinations of specific strength training with identical accumulated volume, and the relevance of training supervision for safe and effective training.</p> <p>Methods/design</p> <p>A cluster randomized controlled trial of 20 weeks duration where employed office workers are randomized to 1 Ă 60 min, 3 Ă 20 min, 9 Ă 7 min per week of specific strength training with training supervision, to 3 Ă 20 min per week of specific strength training with a minimal amount of training supervision, or to a reference group without training. A questionnaire will be sent to 2000 employees in jobs characterized by intensive computer work. Employees with cardiovascular disease, trauma, hypertension, or serious chronic disease will be excluded. The main outcome measure is pain in the neck and shoulders at week 20.</p> <p>Trial Registration</p> <p>The trial is registered at ClinicalTrials.gov, number NCT01027390.</p
Adoptive cancer immunotherapy using DNA-demethylated T helper cells as antigen-presenting cells
A critical determinant of tumor eradication by adoptive immunotherapy is the tumor associated antigen recognized by cytotoxic T lymphocytes. Here the authors generate ex vivo autologous cytotoxic T lymphocytes by exposure to antigens induced by DNA demethylation and report the results of a phase 1 trial of 25 patients with recurrent glioblastoma multiforme with tumor regression in three patients
Identification of a Transcription Factor Controlling pH-Dependent Organic Acid Response in Aspergillus niger.
Acid formation in Aspergillus niger is known to be subjected to tight regulation, and the acid production profiles are fine-tuned to respond to the ambient pH. Based on transcriptome data, putative trans-acting pH responding transcription factors were listed and through knock out studies, mutants exhibiting an oxalate overproducing phenotype were identified. The yield of oxalate was increased up to 158% compared to the wild type and the corresponding transcription factor was therefore entitled Oxalic Acid repression Factor, OafA. Detailed physiological characterization of one of the ÎoafA mutants, compared to the wild type, showed that both strains produced substantial amounts of gluconic acid, but the mutant strain was more efficient in re-uptake of gluconic acid and converting it to oxalic acid, particularly at high pH (pH 5.0). Transcriptional profiles showed that 241 genes were differentially expressed due to the deletion of oafA and this supported the argument of OafA being a trans-acting transcription factor. Furthermore, expression of two phosphoketolases was down-regulated in the ÎoafA mutant, one of which has not previously been described in fungi. It was argued that the observed oxalate overproducing phenotype was a consequence of the efficient re-uptake of gluconic acid and thereby a higher flux through glycolysis. This results in a lower flux through the pentose phosphate pathway, demonstrated by the down-regulation of the phosphoketolases. Finally, the physiological data, in terms of the specific oxygen consumption, indicated a connection between the oxidative phosphorylation and oxalate production and this was further substantiated through transcription analysis
- âŠ