3,110 research outputs found
Die psychosoziale/-sexuelle Entwicklung von Knaben mit einer Hypospadie
Zusammenfassung: Knaben mit einer Hypospadie sind spezifischen psychischen Belastungen im Zusammenhang mit dem chirurgischen Eingriff im Genitalbereich und einem kosmetisch und/oder funktionell beeintrĂ€chtigten Penis ausgesetzt. WĂ€hrend in den letzten Jahrzehnten intensive Anstrengungen zur Verbesserung der Operationstechniken unternommen worden sind, wurde die psychosoziale und psychosexuelle Entwicklung von Kindern und Jugendlichen nach Hypospadiekorrektur erst selten untersucht. Die Resultate der wenigen Studien sind insgesamt sehr widersprĂŒchlich. Sie weisen aber auch deutlich daraufhin, dass die betroffenen Knaben unter spezifischen Problemen wie dem andersartigen Aussehen ihres Penis leiden. Das Angebot von medizinischen Verlaufskontrollen und psychosozialer Beratung muss ihnen deshalb bis ins junge Erwachsenenalter zur VerfĂŒgung gestellt werden. FĂŒr die zukĂŒnftige Forschung gilt es, in methodisch fundierten Studien LebensqualitĂ€t und Entwicklung der Knaben systematisch zu untersuchen. Dabei mĂŒssen insbesondere psychosoziale Risikofaktoren identifiziert werde
Involution of the mouse mammary gland is associated with an immune cascade and an acute-phase response, involving LBP, CD14 and STAT3
INTRODUCTION:
Involution of the mammary gland is a complex process of controlled apoptosis and tissue remodelling. The aim of the project was to identify genes that are specifically involved in this process.
METHODS:
We used Affymetrix oligonucleotide microarrays to perform a detailed transcript analysis on the mechanism of controlled involution after withdrawal of the pups at day seven of lactation. Some of the results were confirmed by semi-quantitative reverse transcriptase polymerase chain reaction, Western blotting or immunohistochemistry.
RESULTS:
We identified 145 genes that were specifically upregulated during the first 4 days of involution; of these, 49 encoded immunoglobulin genes. A further 12 genes, including those encoding the signal transducer and activator of transcription 3 (STAT3), the lipopolysaccharide receptor (CD14) and lipopolysaccharide-binding protein (LBP), were involved in the acute-phase response, demonstrating that the expression of acute-phase response genes can occur in the mammary gland itself and not only in the liver. Expression of LBP and CD14 was upregulated, at both the RNA and protein level, immediately after pup withdrawal; CD14 was strongly expressed in the luminal epithelial cells. Other genes identified suggested neutrophil activation early in involution, followed by macrophage activation late in the process. Immunohistochemistry and histological staining confirmed the infiltration of the involuting mammary tissue with neutrophils, plasma cells, macrophages and eosinophils.
CONCLUSION:
Oligonucleotide microarrays are a useful tool for identifying genes that are involved in the complex developmental process of mammary gland involution. The genes identified are consistent with an immune cascade, with an early acute-phase response that occurs in the mammary gland itself and resembles a wound healing process
Improving the chromatic dispersion tolerance in long-haul fibre links using the coherent optical orthogonal frequency division multiplexing
Numerical simulations of the coherent optical orthogonal frequency division multiplexing modems are undertaken to investigate the effect of the adaptive modulation, the number of sub-carriers, the cyclic prefix (CP) length, the clipping ratio, quantisation bit resolution and the sampling speed of analogue-to-digital converters (ADCs) on the chromatic dispersion (CD) of a single mode fibre (SMF) at data rates up to 80 Gbps. The use of a large number of sub-carriers is more effective in combating fibre dispersion than employing a long CP; moreover, the optimum number of sub-carriers in the presence of both SMF non-linearities and CD has been identified. The authors show that using a high bit resolution ADC with a high clipping ratio, the transmission distance can be increased at specific data rates. Furthermore, it is shown that ADCs with a low sampling speed also improve the system tolerance to the fibre CD. In addition, simulation results show that the use of adaptive modulation schemes improves spectrum usage efficiency, thus resulting in higher tolerance to the CD when compared with the case in which identical modulation formats are adopted across all sub-carriers
Effective T-odd P-even hadronic interactions from quark models
Tests of time reversal symmetry at low and medium energies may be analyzed in
the framework of effective hadronic interactions. Here, we consider the quark
structure of hadrons to make a connection to the more fundamental degrees of
freedom. It turns out that for P-even T-odd interactions hadronic matrix
elements evaluated in terms of quark models give rise to factors of 2 to 5.
Also, it is possible to relate the strength of the anomalous part of the
effective rho-type T-odd P-even tensor coupling to quark structure effects.Comment: 6 pages, 1 figure, RevTe
Genome-wide DNA methylation changes in a mouse model of infection-mediated neurodevelopmental disorders
Background
Prenatal exposure to infectious or inflammatory insults increases the risk of neurodevelopmental disorders. Using a well-established mouse model of prenatal viral-like immune activation, we examined whether this pathological association involves genome-wide DNA methylation differences at single nucleotide resolution.
Methods
Prenatal immune activation was induced by maternal treatment with the viral mimetic polyriboinosinic-polyribocytidylic acid in middle or late gestation. Following behavioral and cognitive characterization of the adult offspring (n = 12 per group), unbiased capture array bisulfite sequencing was combined with subsequent matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and quantitative real-time polymerase chain reaction analyses to quantify DNA methylation changes and transcriptional abnormalities in the medial prefrontal cortex of immune-challenged and control offspring. Gene ontology term enrichment analysis was used to explore shared functional pathways of genes with differential DNA methylation.
Results
Adult offspring of immune-challenged mothers displayed hyper- and hypomethylated CpGs at numerous loci and at distinct genomic regions, including genes relevant for gamma-aminobutyric acidergic differentiation and signaling (e.g., Dlx1, Lhx5, Lhx8), Wnt signaling (Wnt3, Wnt8a, Wnt7b), and neural development (e.g., Efnb3, Mid1, Nlgn1, Nrxn2). Altered DNA methylation was associated with transcriptional changes of the corresponding genes. The epigenetic and transcriptional effects were dependent on the offspring\u2019s age and were markedly influenced by the precise timing of prenatal immune activation.
Conclusions
Prenatal viral-like immune activation is capable of inducing stable DNA methylation changes in the medial prefrontal cortex. These long-term epigenetic modifications are a plausible mechanism underlying the disruption of prefrontal gene transcription and behavioral functions in subjects with prenatal infectious histories
Crystal structures of the carborane dianions, [1,4-(PhCB10H10C)2C6H4]2- and [1,4-(PhCB10H10C)2C6F4]2-, and the stabilizing role of the para-phenylene unit on unusual 2n+3 SE clusters
While carboranes with 2ân+2 and 2ân+4 (n=number of skeletal atoms) skeletal electrons (SE) are widely known, little has been reported on carboranes with odd SE numbers. Electrochemical measurements on two-cage assemblies, where two C-phenyl-ortho-carboranyl groups are linked by a para-phenylene or a para-tetrafluorophenylene bridge, revealed two well separated and reversible two-electron reduction waves indicating formation of stable dianions and tetraanions. The salts of the dianions were isolated by reduction with sodium metal and their unusual structures were determined by X-ray crystallography. The diamagnetic dianions contain two 2ân+3 SE clusters where each cluster has a notably long carborane Câcarborane C distance of ca 2.4 Ă
. The Ï conjugation within the phenylene bridge plays an important role in the stabilization of these carboranes with odd SE counts
Performance of Hamamatsu 64-anode photomultipliers for use with wavelength--shifting optical fibres
Hamamatsu R5900-00-M64 and R7600-00-M64 photomultiplier tubes will be used
with wavelength--shifting optical fibres to read out scintillator strips in the
MINOS near detector. We report on measurements of the gain, efficiency,
linearity, crosstalk, and dark noise of 232 of these PMTs, of which 219 met
MINOS requirements.Comment: 15 pages, 12 figures. Accepted by Nucl. Inst. Meth.
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Modeling and High-Resolution-Imaging Studies of Water-Content Profiles in a Polymer-Electrolyte-Fuel-Cell Membrane-Electrode Assembly
Water-content profiles across the membrane electrode assembly of a polymer-electrolyte fuel cell were measured using high-resolution neutron imaging and compared to mathematical-modeling predictions. It was found that the membrane held considerably more water than the other membrane-electrode constituents (catalyst layers, microporous layers, and macroporous gas-diffusion layers) at low temperatures, 40 and 60 C. The water content in the membrane and the assembly decreased drastically at 80 C where vapor transport and a heat-pipe effect began to dominate the water removal from the membrane-electrode assembly. In the regimes where vapor transport was significant, the through-plane water-content profile skewed towards the cathode. Similar trends were observed as the relative humidity of the inlet gases was lowered. This combined experimental and modeling approach has been beneficial in rationalizing the results of each and given insight into future directions for new experimental work and refinements to currently available models
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