Pyrrolizidine alkaloids (PA) and PA -oxides (PANO) are secondary plant metabolites exhibiting genotoxic and carcinogenic properties. Apart from the roots and leaves, PA/PANO are particularly present in pollen and nectar. Therefore, the spread of in certain regions of northern Germany has an impact on the safety of honey produced in that region.
View Article and Find Full Text PDFClin Pract Cases Emerg Med
August 2019
We report a case of polymethylmethacrylate cement pulmonary embolism (PE) that occurred two days following a minimally invasive kyphoplasty procedure. Our patient developed non-specific rib pain postoperatively followed by dyspnea, prompting presentation to the emergency department. The polymethylmetacrylate cement was visualized on initial chest radiograph and further characterized using computed tomography.
View Article and Find Full Text PDFWe describe time-resolved measurements of the evolution of the spectrum of radiation emitted by an optically-pumped continuous-wave InGaAs-GaAs quantum well laser, recorded as lasing builds up from noise to steady state. We extract a fitting parameter corresponding to the gain dispersion of the parabolic spectrum equal to -79 ± 30 fs2 and -36 ± 6 fs2 for a resonant and anti-resonant structure, respectively. Furthermore the recorded evolution of the spectrum allows for the calculation of an effective FWHM gain bandwidth for each structure, of 11 nm and 18 nm, respectively.
View Article and Find Full Text PDFThe clinical significance of the presence of Clostridium difficile in children's faeces remains uncertain using current diagnostic procedures. Clostridium difficile is a relatively common finding in infants with no symptoms of gastrointestinal disease, suggesting it may be an incidental finding and form part of the normal gut micro-flora in this age group. On the other hand, particularly in older children or those with significant co-morbidity, there are examples where C.
View Article and Find Full Text PDFThe properties of the connections made by the axons of pyramidal cells with cortico-thalamic (CT)-like morphology with a range of postsynaptic layer 6 targets were studied with dual intracellular recordings in slices of adult rat and cat neocortex. The cells were filled with biocytin and identified morphologically and, where appropriate, immunofluorescently. CT-like pyramids contacted interneurons with a very high probability (up to 1:2) but contacted other layer 6 pyramidal cells only rarely (approximately 1:80).
View Article and Find Full Text PDFPaired intracellular recordings with biocytin labelling were made in slices of adult rat somatosensory and visual cortex and in cat visual cortex to examine the properties of synaptic connections made by layer 6 pyramidal cells, to determine whether cortico-cortical pyramids more commonly provide input to other layer 6 pyramids than cortico-thalamic cells, and whether these connections exhibit paired pulse and brief train depression. Pyramidal cells with cortico-cortical like morphology were 2-4 times more likely to innervate other pyramidal cells than were cortico-thalamic like cells, but less likely to innervate inhibitory interneurons. The excitatory postsynaptic potentials elicited by presynaptic, phasically firing cortico-cortical pyramids in all classes of postsynaptic infragranular layer pyramidal cells exhibited strong, presynaptically mediated paired pulse and brief train depression.
View Article and Find Full Text PDFJ Neurocytol
September 2003
In this brief review of inter-laminar synaptic connections in neocortex a case is made for the hypothesis that axons select their targets, or neurones select their inputs with great specificity. A large part of the data discussed was obtained from dual intracellular recordings in slices of adult neocortex. The neurones innervated in a given layer by a given type of axon were not found to be a random selection of the cells in that layer.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
December 2002
We attempt to summarize the properties of cortical synaptic connections and the precision with which they select their targets in the context of information processing in cortical circuits. High-frequency presynaptic bursts result in rapidly depressing responses at most inputs onto spiny cells and onto some interneurons. These 'phasic' connections detect novelty and changes in the firing rate, but report frequency of maintained activity poorly.
View Article and Find Full Text PDFBush crickets have long, thin hind legs but jump and kick rapidly. The mechanisms underlying these fast movements were analysed by correlating the activity of femoral muscles in a hind leg with the movements of the legs and body captured in high-speed images. A female Pholidoptera griseoaptera weighing 600 mg can jump a horizontal distance of 300 mm from a takeoff angle of 34 degrees and at a velocity of 2.
View Article and Find Full Text PDFThe Thailand winged stick insect (Sipyloidea sp.) flees rapidly from a disturbance by jumping forwards when stimulated on the abdomen and backwards when stimulated on the head. The mechanisms underlying these fast movements were analysed by measuring movements of the body and legs from images captured at 250 Hz.
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