The microRNA pathway has been implicated in the regulation of synaptic protein synthesis and ultimately in dendritic spine morphogenesis, a phenomenon associated with long-lasting forms of memory. ...However, the particular microRNAs (miRNAs) involved are largely unknown. Here we identify specific miRNAs that function at synapses to control dendritic spine structure by performing a functional screen. One of the identified miRNAs, miR-138, is highly enriched in the brain, localized within dendrites and negatively regulates the size of dendritic spines in rat hippocampal neurons. miR-138 controls the expression of acyl protein thioesterase 1 (APT1), an enzyme regulating the palmitoylation status of proteins that are known to function at the synapse, including the alpha(13) subunits of G proteins (Galpha(13)). RNA-interference-mediated knockdown of APT1 and the expression of membrane-localized Galpha(13) both suppress spine enlargement caused by inhibition of miR-138, suggesting that APT1-regulated depalmitoylation of Galpha(13) might be an important downstream event of miR-138 function. Our results uncover a previously unknown miRNA-dependent mechanism in neurons and demonstrate a previously unrecognized complexity of miRNA-dependent control of dendritic spine morphogenesis.
The forensic luminol test is used to screen large areas for the presence of blood. The heme-induced reduction of hydrogen peroxide is coupled to the oxidation of luminol resulting in luminescence. ...However, photographic documentation of the relatively weak and short-lived luminescence is difficult and luminol is now often replaced by other chemicals. In this study, we investigated reports from the Rostock police department that the addition of "Fit", a dishwashing detergent from former Eastern Germany, could both intensify and prolong the luminescence of luminol on blood stains. Even though this effect was reported only for the original composition of Fit but not the currently sold version, we found that both the old and the new version of Fit increase the brightness of the luminescence while decreasing its duration. This may be due to detergents in the dishwashing liquid, which permeabilize the plasma membrane of the erythrocytes, exposing the Fe3+ inside the cell and speeding up the entire reaction. We did not find any evidence of special ingredients in the old version of Fit that would cause both the increased brightness and prolonged duration of luminescence as reported by the Rostock PD.
The gallbladder is an uncommon site of metastatic cancer. Although ultrasound can be regarded as a first line investigation for the detection of gallbladder lesions, differentiation between benign ...and malignant tumors usually requires resection. Real-time contrast enhanced ultrasound (CEUS) is a well-established technique for the classification of liver, pancreatic, and renal diseases (Weskott, 2008). The application of CEUS in the diagnosis of gallbladder tumors has rarely been described. We report the application of contrast enhanced ultrasound for the characterization of a gallbladder lesion in a 63-year-old patient with a history of renal cell and rectal cancer.
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