13 research outputs found
Schizophrenia is associated with an increase in cortical microRNA biogenesis
MicroRNA expression profiling and quantitative reverse transcription-PCR analysis of the superior temporal gyrus and the dorsolateral prefrontal cortex revealed a significant schizophrenia-associated increase in global microRNA expression. This change was associated with an elevation of primary microRNA processing and corresponded with an increase in the microprocessor component DGCR8. The biological implications for this extensive increase in gene silencing are profound, and were exemplified by members of the miR-15 family and other related microRNA, which were significantly upregulated in both brain regions. This functionally convergent influence is overrepresented in pathways involved in synaptic plasticity and includes many genes and pathways associated with schizophrenia, some of which were substantiated in vitro by reporter gene assay. Given the magnitude of microRNA changes and their wide sphere of influence, this phenomenon could represent an important dimension in the pathogenesis of schizophrenia
Schizophrenia and reelin: a model based on prenatal stress to study epigenetics, brain development and behavior
Individual and environmental determinants of Cuterebra bot fly parasitism in the eastern chipmunk (Tamias striatus)
The relationship between reading and listening comprehension: shared and modality-specific components
Electrophysiological evidence for abnormal glutamate-GABA association following psychosis onset
Gradient sensing in defined chemotactic fields
Cells respond to a variety of secreted molecules by modifying their physiology, growth patterns, and behavior. Motile bacteria and eukaryotic cells can sense extracellular chemoattractants and chemorepellents and alter their movement. In this way fibroblasts and leukocytes can find their ways to sites of injury and cancer cells can home in on sites that are releasing growth factors. Social amoebae such as Dictyostelium are chemotactic to cAMP which they secrete several hours after they have initiated development. These eukaryotic cells are known to be able to sense extremely shallow gradients but the processes underlying their exquisite sensitivity are still largely unknown. In this study we determine the responses of developed cells of Dictyostelium discoideum to stable linear gradients of cAMP of varying steepness generated in 2 µm deep gradient chambers of microfluidic devices. The gradients are generated by molecular diffusion between two 50 µm deep flow-through channels, one of which is perfused with a solution of cAMP and the other with buffer, serving as continuously replenished source and sink. These low ceiling gradient chambers constrained the cells in the vertical dimension, facilitatin