13 research outputs found
Synovitis and bone inflammation in early rheumatoid arthritis: high-resolution multi-pinhole SPECT versus MRI
PURPOSEWe aimed to assess the relationship between bone inflammation in multi-pinhole single-photon emission computed tomography (MPH-SPECT) and synovitis detected by magnetic resonance imaging (MRI) in early rheumatoid arthritis patients. MATERIALS AND METHODSMPH-SPECT with technetium dicarboxypropanedisphosphonate (Tc-99mDPD) and 3 Tesla MRI were performed in 10 early rheumatoid arthritis patients. Eighty finger joint sites were assessed for increased osteoblastic activity using visual and region-of-interest (ROI) analysis. Presence of joint inflammation in MRI was investigated using the subscores of the rheumatoid arthritis MRI score. RESULTSTc-99mDPD uptake was increased in 38 (47.5%) and 22 (27.5%) joint sites as determined by visual and ROI analysis, respectively. A total of 32 (84.2%) sites with increased bone metabolism showed a normal MRI bone signal. The MPHSPECT uptake ratio was elevated only in the subgroup with severe synovitis (P < 0.001). CONCLUSIONIn early rheumatoid arthritis, molecular imaging with MPHSPECT detects higher rates of inflammatory bone involvement compared to MRI. Our preliminary data suggest that osteitis is related to severe synovitis
Time Dependence of Fluoride Uptake in Hydroxyapatite
Fluoridation
of enamel is believed to provide an effective tool
to protect teeth from caries, but there is still little information
on the time scale of fluoride uptake. In this study, highly compressed
pellets of hydroxyapatite are used as first-order model systems to
approximate the mineral component of natural enamel for investigations
on the time-dependence of fluoride uptake. We found that both the
overall amount of fluoride as well as the mean thickness of the fluoridated
surface layer cannot be extended to any values just by increasing
the application time of a fluoride containing agent. Instead, both
parameters start to become constant on a time scale of about 3 min.
The present results as obtained on a synthetic model “tooth”
show that the time scale to provide the maximum amount of fluoride
possible is of the same order of magnitude as that in usual daily
practice in dental care when applying toothpastes or mouth rinses
Parameterization of Thermal Properties of Aging Secondary Organic Aerosol Produced by Photo-Oxidation of Selected Terpene Mixtures
Formation and evolution of secondary
organic aerosols (SOA) from
biogenic VOCs influences the Earth’s radiative balance. We
have examined the photo-oxidation and aging of boreal terpene mixtures
in the SAPHIR simulation chamber. Changes in thermal properties and
chemical composition, deduced from mass spectrometric measurements,
were providing information on the aging of biogenic SOA produced under
ambient solar conditions. Effects of precursor mixture, concentration,
and photochemical oxidation levels (OH exposure) were evaluated. OH
exposure was found to be the major driver in the long term photochemical
transformations, i.e., reaction times of several hours up to days,
of SOA and its thermal properties, whereas the initial concentrations
and terpenoid mixtures had only minor influence. The volatility distributions
were parametrized using a sigmoidal function to determine <i>T</i><sub>VFR0.5</sub> (the temperature yielding a 50% particle
volume fraction remaining) and the steepness of the volatility distribution. <i>T</i><sub>VFR0.5</sub> increased by 0.3 ± 0.1% (ca. 1 K),
while the steepness increased by 0.9 ± 0.3% per hour of 1 ×
10<sup>6</sup> cm<sup>–3</sup> OH exposure. Thus, aging reduces
volatility and increases homogeneity of the vapor pressure distribution,
presumably because highly volatile fractions become increasingly susceptible
to gas phase oxidation, while less volatile fractions are less reactive
with gas phase OH
<i>Corynebacterium glutamicum</i> Chassis C1*: Building and Testing a Novel Platform Host for Synthetic Biology and Industrial Biotechnology
Targeted
top-down strategies for genome reduction are considered
to have a high potential for providing robust basic strains for synthetic
biology and industrial biotechnology. Recently, we created a library
of 26 genome-reduced strains of <i>Corynebacterium glutamicum</i> carrying broad deletions in single gene clusters and showing wild-type-like
biological fitness. Here, we proceeded with combinatorial deletions
of these irrelevant gene clusters in two parallel orders, and the
resulting library of 28 strains was characterized under various environmental
conditions. The final chassis strain C1* carries a genome reduction
of 13.4% (412 deleted genes) and shows wild-type-like growth behavior
in defined medium with d-glucose as carbon and energy source.
Moreover, C1* proves to be robust against several stresses (including
oxygen limitation) and shows long-term growth stability under defined
and complex medium conditions. In addition to providing a novel prokaryotic
chassis strain, our results comprise a large strain library and a
revised genome annotation list, which will be valuable sources for
future systemic studies of <i>C. glutamicum</i>
Observation of decays and precision measurements of the masses
International audienceThe first observation of the decays B(s)0→J/ψpp¯ is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2 fb-1, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are B(B0→J/ψpp¯)=[4.51±0.40(stat)±0.44(syst)]×10-7, B(Bs0→J/ψpp¯)=[3.58±0.19(stat)±0.39(syst)]×10-6. For the Bs0 meson, the result is much higher than the expected value of O(10-9). The small available phase space in these decays also allows for the most precise single measurement of both the B0 mass as 5279.74±0.30(stat)±0.10(syst) MeV and the Bs0 mass as 5366.85±0.19(stat)±0.13(syst) MeV
Genome-wide meta-analysis of over 29,000 people with epilepsy reveals 26 loci and subtype-specific genetic architecture
AbstractEpilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here, we report a trans-ethnic GWAS including 29,944 cases, stratified into three broad- and seven sub-types of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants substantially close the missing heritability gap for GGE. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analysis of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current anti-seizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment