Mir-132/212 is required for maturation of binocular matching of orientation preference and depth perception

MicroRNAs (miRNAs) are known to mediate post-transcriptional gene regulation, but their role in postnatal brain development is still poorly explored. We show that the expression of many miRNAs is dramatically regulated during functional maturation of the mouse visual cortex with miR-132/212 family being one of the top upregulated miRNAs. Age-downregulated transcripts are significantly enriched in miR-132/miR-212 putative targets and in genes upregulated in miR-132/212 null mice. At a functional level, miR-132/212 deletion affects development of receptive fields of cortical neurons determining a specific impairment of binocular matching of orientation preference, but leaving orientation and direction selectivity unaltered. This deficit is associated with reduced depth perception in the visual cliff test. Deletion of miR-132/212 from forebrain excitatory neurons replicates the binocular matching deficits. Thus, miR-132/212 family shapes the age-dependent transcriptome of the visual cortex during a specific developmental window resulting in maturation of binocular cortical cells and depth perception

Developmental Expression of Kv Potassium Channels at the Axon Initial Segment of Cultured Hippocampal Neurons

Axonal outgrowth and the formation of the axon initial segment (AIS) are early events in the acquisition of neuronal polarity. The AIS is characterized by a high concentration of voltage-dependent sodium and potassium channels. However, the specific ion channel subunits present and their precise localization in this axonal subdomain vary both during development and among the types of neurons, probably determining their firing characteristics in response to stimulation. Here, we characterize the developmental expression of different subfamilies of voltage-gated potassium channels in the AISs of cultured mouse hippocampal neurons, including subunits Kv1.2, Kv2.2 and Kv7.2. In contrast to the early appearance of voltage-gated sodium channels and the Kv7.2 subunit at the AIS, Kv1.2 and Kv2.2 subunits were tethered at the AIS only after 10 days in vitro. Interestingly, we observed different patterns of Kv1.2 and Kv2.2 subunit expression, with each confined to distinct neuronal populations. The accumulation of Kv1.2 and Kv2.2 subunits at the AIS was dependent on ankyrin G tethering, it was not affected by disruption of the actin cytoskeleton and it was resistant to detergent extraction, as described previously for other AIS proteins. This distribution of potassium channels in the AIS further emphasizes the heterogeneity of this structure in different neuronal populations, as proposed previously, and suggests corresponding differences in action potential regulation

AAFP and ISFM Guidelines for Diagnosing and Solving House-Soiling Behavior in Cats

RATIONALE: These Guidelines have been developed by the American Association of Feline Practitioners (AAFP) and the International Society of Feline Medicine (ISFM) as a resource for veterinary practitioners who want to better understand and manage the important clinical condition of house-soiling in their feline patients. The Guidelines offer straightforward, practical solutions that, in most cases, will help veterinarians and cat owners prevent, manage or entirely remediate feline house-soiling behavior. EVIDENCE BASE: The Guidelines include scientifically documented information when it is available. However, because research is often lacking, some recommendations reflect the accumulated clinical experience of the authors

Predicting the geomorphological responses of gravel-bed rivers to flow and sediment source perturbations at the watershed scale: an application in an Alpine watershed

Predicting morphological channel changes using physically-based models requires extended data for the description of the river channel and for hydrological and sedimentological inputs. At the watershed scale, these data are usually scarce, and such a refined modeling is typically difficult to build. A simpler modeling of the morphological impacts due to the changes in the principal drivers that control channel shape and dynamics is more adaptable. In this study we focused on the morphological responses of gravel-bed rivers to flow and sediment source perturbation at watershed scale. The aim is to develop and test a tool capable of semi-quantitatively predicting the morphological river response at the watershed scale due to a set of spatially distributed perturbations. The model considers flow regime (Q) and sediment supply (S) as the two main factors controlling the fluvial morphology in alluvial rivers. Two indicators have been proposed to evaluate the alteration on Q and S, and they are illustrated as vectors on each reach of the river network. The magnitude of the vectors corresponds to the intensity of the perturbation and its direction represents the changing trend that nine selected morphological variables (bed elevation, slope, width, depth, wetted area, width to depth ratio, d50, terrace formation, and colonization of vegetation) are likely to follow from an initial state. The trends or trajectories of changes were assessed based on empirical relations, case studies, and conceptual models. This method was applied to the Isère watershed (5700 km2) at Grenoble (France), a river that hosts large and complex hydropower plant systems constructed during 50s -70s. The predictions over 23 river reaches and eight variables were evaluated in the range where the model was capable of predicting the morphological evolution of the river system. Its performance was verified and in the majority of the cases the results were coherent with field surveys and previous observations. The results indicate that this is a complex problem which needs more careful consideration of constraints that are difficult to assess, such as simultaneous and different sources of perturbations, hypotheses of initial dynamic equilibrium, and sediment supply quantificatio