Gramarcher5304
Compared to intake on a day when no inhibition was given, postmeal inhibition of dHC glutamatergic neurons given for 10 min after the end of a saccharin meal increased the likelihood that rats would consume a second meal 90 min later and significantly increased the amount of saccharin solution consumed during that next meal when the neurons were no longer inhibited. Importantly, delayed inhibition given 80 min after the end of the saccharin meal did not affect subsequent intake of saccharin. Given that saccharin has minimal postingestive gastric consequences, these effects are not likely due to the timing of interoceptive visceral cues generated by the meal. These data show that dHC glutamatergic neural activity is necessary during the early postprandial period for limiting future intake and suggest that these neurons inhibit future intake by consolidating the memory of the preceding meal.Place memory, the ability to remember locations, is a feature of many animal species. This episodic-like memory is displayed in the foraging behavior of animals and has been studied in many different kinds of laboratory spatial tasks. Sovilnesib nmr A horse stallion, Equus ferus caballus, will create "dung-heaps or stud-piles" by defecation in the same place suggesting that the behavior is central to spatial behavior but to date there has been little investigation of horse olfactory/spatial behavior. The present study describes investigatory behavior of horses for objects on the surface of a riding arena. Horses under saddle approached objects on the arena surface that included small pieces of straw, fur, and paper and larger objects including clumps of debris and were especially interested in dung droppings left by other horses. Once an object was investigated by sniffing, it was usually not approached again during that outing but could be approached anew on the following day. Dung investigatory behavior and place memory were confirmed in a number of structured tests in which test-retest intervals were varied. The results are discussed in relation to the dual process theory that proposes that spatial representations central to adaptive behavior require both allocentric Cartesian spatial information and egocentric episodic-like information.Decades of experimental and theoretical work support a now well-established theory that active dendritic processing contributes to the computational power of individual neurons. This theory is based on the high degree of electrical compartmentalization observed in the dendrites of single neurons in ex vivo preparations. Compartmentalization allows dendrites to conduct semi-independent operations on their inputs before final integration and output at the axon, producing a "network-in-a-neuron." However, recent in vivo functional imaging experiments in mouse cortex have reported surprisingly little evidence for strong dendritic compartmentalization. In this review, we contextualize these new findings and discuss their impact on the future of the field. Specifically, we consider how highly coordinated, and thus less compartmentalized, activity in soma and dendrites can contribute to cortical computations including nonlinear mixed selectivity, prediction/expectation, multiplexing, and credit assignment.Neuropeptides are expected as therapeutic drug candidates for central nervous system (CNS) disorders. Intracerebroventricular (i.c.v.) administration of glucagon-like peptide-2 (GLP-2) has an antidepressant-like effect not only in depression model mice but also in treatment-resistant depression model mice. However, because i.c.v. administration is very invasive, research is progressing on brain delivery using intranasal administration as a non-invasive method. After intranasal administration of the drug, there are two routes to the brain. That of direct delivery from the paracellular route of olfactory epithelium to the brain via the olfactory bulb has been studied, and that of systemic absorption via the paracellular route of respiratory epithelium has been put to practical use. The high degree of vascularization and permeability of the nasal mucosa enables drug delivery via the paracellular route that leads to systemic delivery. Therefore, suppressing systemic absorption may increase drug delivery to brain,intravenous administered PAS-CPP-GLP-2 did not show the effect. These results suggested that PAS-CPP-GLP-2 can be efficiently delivered from the nose to the CNS and show a pharmacological effect, demonstrating the usefulness of PAS and CPP for nose-to-brain delivery of GLP-2.The development of cell microencapsulation systems began several decades ago. However, today few systems have been tested in clinical trials. For this reason, in the last years, researchers have directed efforts towards trying to solve some of the key aspects that still limit efficacy and biosafety, the two major criteria that must be satisfied to reach the clinical practice. Regarding the efficacy, which is closely related to biocompatibility, substantial improvements have been made, such as the purification or chemical modification of the alginates that normally form the microspheres. Each of the components that make up the microcapsules has been carefully selected to avoid toxicities that can damage the encapsulated cells or generate an immune response leading to pericapsular fibrosis. As for the biosafety, researchers have developed biological circuits capable of actively responding to the needs of the patients to precisely and accurately release the demanded drug dose. Furthermore, the structure of the devices has been subject of study to adequately protect the encapsulated cells and prevent their spread in the body. The objective of this review is to describe the latest advances made by scientist to improve the efficacy and biosafety of cell microencapsulation systems for sustained drug delivery, also highlighting those points that still need to be optimized.
MR fingerprinting (MRF) is a versatile method for rapid multi-parametric quantification. The application of MRF for lower MRI field could enable multi-contrast imaging and improve exam efficiency on these systems. The purpose of this work is to demonstrate the feasibility of 3D whole-brain T1 and T2 mapping using MR fingerprinting on a contemporary 0.55T MRI system.
A 3D whole brain stack-of-spirals FISP MRF sequence was implemented for 0.55T. Quantification was validated using the NIST/ISMRM Quantitative MRI phantom, and T1 and T2 values of white matter, gray matter, and cerebrospinal fluid were measured in 19 healthy subjects. To assess MRF performance in the lower SNR regime of 0.55T, measurement precision was calculated from 100 simulated pseudo-replicas of in vivo data and within-session measurement repeatability was evaluated.
T1 and T2 values calculated by MRF were strongly correlated to standard measurements in the ISMRM/NIST MRI system phantom (R
>0.99), with a small constant bias of approximately 5ms in T2 values.