How much of the remarkable variation in neuron number within a species is generated by genetic differences, and how much is generated by environmental factors? We address this problem for a single population of neurons in the mouse CNS. Retinal ganglion cells of inbred and outbred strains, wild species and subspecies, and F1 hybrids were studied using an unbiased electron microscopic method wit...

Genomic imprinting is a phenomenon whereby monoallelic gene expression occurs in a parent-of-origin-specific manner. A subset of imprinted genes acquires a tissue-specific imprinted status during the course of tissue development, and this process can be analyzed by means of an in vitro differentiation system utilizing embryonic stem (ES) cells. In neurons, the gene Ube3a is expressed from the m...

The Rhagoletis pomonella species complex is one of the foremost examples supporting the occurrence of sympatric speciation. A recent study found that reciprocal F(1) hybrid offspring from different host plant-infesting populations in the complex displayed significantly reduced olfactory host preference in flight-tunnel assays. Behavioral and electrophysiological studies indicate that olfactory ...

the aim of the present study was to examine the effect of grafting of watermelon hybrids ‘obla f1’ and ‘vanessa f1’ on to cucurbita maxima × cucurbita moschata rootstock tz 148 and lagenaria sp. rootstock ‘dias f1’, on the volatiles and yield of fruit and the plant growth. fruit volatiles analysis showed the presence of two aldehydes, namely (e)-2-nonenal and (e,z)-2,6-nonadien-1-al, with (e)-2...

Synaptic vesicles are released stochastically, and therefore stimuli that increase a neuron's synaptic input might increase noise at its spike output. Indeed this appears true for neurons in primary visual cortex, where spike output variability increases with stimulus contrast. But in retinal ganglion cells, although intracellular recordings (with spikes blocked) showed that stronger stimuli in...

During auditory stimulation with several frequency components, distortion products (DPs) are generated as byproduct of nonlinear cochlear amplification. After generated, DP energy is reemitted into the ear channel where it can be measured as DP otoacoustic emission (DPOAE), and it also induces an excitatory response at cochlear places related to the DP frequencies. We measured responses of 91 i...

Introduction: The induction of human umbilical cord-derived mesenchymal stem cells (HUC-MSCs) toward dopaminergic neurons is a major challenge in tissue engineering and experimental and clinical treatments of various neurodegenerative diseases, including Parkinson disease. This study aims to differentiate HUC-MSCs into dopaminergic neuron-like cells. Methods: Following the isolation and charac...

We have recorded single-neuron activity from cytoarchitectonic area 18 of anesthetized (0.4-0.7% isoflurane in 65% N₂O-35% O₂ gaseous mixture) domestic cats. Neurons were identified as simple or complex on the basis of the ratios between the phase-variant (F1) component and the mean firing rate (F0) of spike responses to optimized (orientation, direction, spatial and temporal frequencies, size)...