51 research outputs found
qualifying label components for effective biosensing using advanced high throughput seira methodology
The multiplexed SEIRA analysis of antibody-functionalized NP biolabels that can be exploited for specific assay platforms in view of high-performance readout
Nanoscale plasmonic phenomena in CVD-grown MoS2 monolayer revealed by ultra- broadband synchrotron radiation based nano-FTIR spectroscopy and near-field microscopy
Nanoscale plasmonic phenomena observed in single and bi-layers of molybdenum
disulfide (MoS2) on silicon dioxide (SiO2) are reported. A scattering type
scanning near-field optical microscope (s-SNOM) with a broadband synchrotron
radiation (SR) infrared source was used. We also present complementary optical
mapping using tunable CO2-laser radiation. Specifically, there is a
correlation of the topography of well-defined MoS2 islands grown by chemical
vapor deposition, as determined by atomic force microscopy, with the infrared
(IR) signature of MoS2. The influence of MoS2 islands on the SiO2 phonon
resonance is discussed. The results reveal the plasmonic character of the MoS2
structures and their interaction with the SiO2 phonons leading to an
enhancement of the hybridized surface plasmon-phonon mode. A theoretical
analysis shows that, in the case of monolayer islands, the coupling of the
MoS2 optical plasmon mode to the SiO2 surface phonons does not affect the
infrared spectrum significantly. For two-layer MoS2, the coupling of the extra
inter-plane acoustic plasmon mode with the SiO2 surface transverse phonon
leads to a remarkable increase of the surface phonon peak at 794 cm−1. This is
in agreement with the experimental data. These results show the capability of
the s-SNOM technique to study local multiple excitations in complex non-
homogeneous structures
Голодомор 1932 –– 1933 рр. в Україні як геноцид
Given its fundamental role in development and cancer, the Wnt-beta-catenin signaling pathway is tightly controlled at multiple levels. RING finger protein 43 (RNF43) is an E3 ubiquitin ligase originally found in stem cells and proposed to inhibit Wnt signaling by interacting with the Wnt receptors of the Frizzled family. We detected endogenous RNF43 in the nucleus of human intestinal crypt and colon cancer cells. We found that RNF43 physically interacted with T cell factor 4 (TCF4) in cells and tethered TCF4 to the nuclear membrane, thus silencing TCF4 transcriptional activity even in the presence of constitutively active mutants of beta-catenin. This inhibitory mechanism was disrupted by the expression of RNF43 bearing mutations found in human gastrointestinal tumors, and transactivation of the Wnt pathway was observed in various cells and in Xenopus embryos when the RING domain of RNF43 was mutated. Our findings indicate that RNF43 inhibits the Wnt pathway downstream of oncogenic mutations that activate the pathway. Mimicking or enhancing this inhibitory activity of RNF43 may be useful to treat cancers arising from aberrant activation of the Wnt pathwa
Validation of a Novel Immunoline Assay for Patient Stratification according to Virulence of the Infecting Helicobacter pylori Strain and Eradication Status
Helicobacter pylori infection shows a worldwide prevalence of around 50%. However, only a minority of infected individuals develop clinical symptoms or diseases. The presence of H. pylori virulence factors, such as CagA and VacA, has been associated with disease development, but assessment of virulence factor presence requires gastric biopsies. Here, we evaluate the H. pylori recomLine test for risk stratification of infected patients by comparing the test score and immune recognition of type I or type II strains defined by the virulence factors CagA, VacA, GroEL, UreA, HcpC, and gGT with patient's disease status according to histology. Moreover, the immune responses of eradicated individuals from two different populations were analysed. Their immune response frequencies and intensities against all antigens except CagA declined below the detection limit. CagA was particularly long lasting in both independent populations. An isolated CagA band often represents past eradication with a likelihood of 88.7%. In addition, a high recomLine score was significantly associated with high-grade gastritis, atrophy, intestinal metaplasia, and gastric cancer. Thus, the recomLine is a sensitive and specific noninvasive test for detecting serum responses against H. pylori in actively infected and eradicated individuals. Moreover, it allows stratifying patients according to their disease state
Terahertz pump-probe experiment at the synchrotron light source MLS
We have developed a pump-probe experiment utilizing broad-band coherent terahertz synchrotron radiation provided by the Metrology Light Source (MLS). The design, performance and first results obtained with the setup are presented
Metrologie mit Synchrotronstrahlung – eine kurze Einführung
PTB-Mitteilungen. Band 124 (2014), Heft 3, Seite 3 - 6. ISSN 0030-834
Die Elektronenspeicherringe MLS und BESSY II als primäre Strahlernormale
PTB-Mitteilungen. Band 124 (2014), Heft 3, Seite 7 - 15. ISSN 0030-834
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