Examining the contribution of surrounding intact skin during cutaneous healing

Severe cutaneous wounds expose the body to the external environment, which may lead to impairments in bodily functions and increased risk of infection. There is a need to develop skin substitutes which could effectively promote complete skin regeneration following an injury. Murine models are used to test such skin substitutes, but their healing involves contraction of the dermis not found in human wounds. We have previously described a device called a dome, which comes in two models, that is used to prevent skin contraction in mice. One model provides a physical barrier to minimize contraction, and the other model has additional perforations in the barrier to allow cellular contribution from the surrounding intact skin. Taking advantage of an enhanced version of these two models, we compared granulation tissue formation, the extent of vascularization, and the transition to myofibroblastic phenotype between the models. We enhanced the dome by developing a twist open cap dome and applied the two models of the dome into the excisional wound biopsy in mice. We demonstrate that the dome can be used to prevent skin contraction in mice. The control model prevented skin contraction while barricading the contribution of surrounding intact skin. When not barricaded, the intact skin enhances wound healing by increasing the number of myofibroblasts and neovascularization. Using a novel model of inhibition of skin contraction in rodents, we examined the contribution from the surrounding intact skin to granulation tissue formation, myofibroblastic differentiation, and neovascularization during the course of skin healing in mice.     

Screening the full leucocyte receptor complex genomic region revealed associations with pemphigus that might be explained by gene regulation

Pemphigus foliaceus (PF) is a blistering autoimmune skin disease rare in most of the world but endemic in certain regions of Brazil. PF is characterized by the detachment of epidermal cells and the presence of autoantibodies against desmoglein 1. In previous studies, we have shown that genetic polymorphisms and variable expression levels of certain leucocyte receptor complex (LRC) genes were associated with PF. However, the role of the LRC on PF susceptibility remained to be investigated. Here, we analysed 527 tag single nucleotide polymorphisms (SNPs) distributed within the 1·5 Mb LRC. After quality control, a total of 176 SNPs were analysed in 229 patients with PF and 194 controls. Three SNPs were associated with differential susceptibility to PF. The intergenic variant rs465169 [odds ratio (OR) = 1·50; P = 0·004] is located in a region that might regulate several immune-related genes, including VSTM1, LILRB1/2, LAIR1/2, LILRA3/4 and LENG8. The rs35336528 (OR = 3·44; P = 0·009) and rs1865097 (OR = 0·57; P = 0·005) SNPs in LENG8 and FCAR genes, respectively, were also associated with PF. Moreover, we found four haplotypes with SNPs within the KIR3DL2/3, LAIR2 and LILRB1 genes associated with PF (P < 0·05), which corroborate previously reported associations. Thus, our results confirm the importance of the LRC for differential susceptibility to PF and reveal new markers that might influence expression levels of several LRC genes, as well as candidates for further functional studies.     

An Optogenetic Study of the Electrophysiological Properties of Hippocampal Neurons in PS1-M146V Transgenic Mice (a model of Alzheimer’s disease)

Neuroscience and Behavioral Physiology - We report here a comparative (using chemical, electrical, and optical stimulation) study of the electrophysiological properties of cultured hippocampal...     

Propagation of Endogenous Electric Fields as a Possible Mechanism of Synchronization of Interictal Spikes in the Rat Neocortex

Neuroscience and Behavioral Physiology - The effects of weak electric fields with parameters close to those of the electrical activity of brain structures on neural networks in the brain have been...     

Germinal center B cell initiation,GC maturation,and the coevolution of its stromal cell niches

Throughout the developing GC response, B cell survival and fate choices made at the single cell level are dependent on signals received largely through interactions with other cells, often with cognate T cells. The type of signals that a given B cell can encounter is dictated by its location within tissue microarchitecture. The focus of this review is on the initiation and evolution of the GC response at the earliest time points. Here, we review the key factors influencing the progression of GC B cell differentiation that are both stage and context dependent. Finally, we describe the coevolution of niches within and surrounding the GC that influence the outcome of the GC response.     

Effects of the Interaction of the ANKK1/DRD2 TaqIA and HTR2C Cys23Ser Polymorphisms on Approach Motivation in Schizophrenia Patients and Healthy People

Neuroscience and Behavioral Physiology - Objective. To assess the association of the DRD2 gene and its interaction with the HTR2C gene with the characteristics of the hedonistic and activatory...     

Use of Anchoring Motifs to Support the Central and Peripheral Locations of Opsins in Optogenetics

Neuroscience and Behavioral Physiology - One version of the optogenetic prosthetization of the degenerative retina is an approach based on creation of an ON/OFF receptive field for ganglion neurons...     

Learning with Reinforcement: the Role of Immediate Feedback and the Internal Model of the Situation

Neuroscience and Behavioral Physiology - Human behavior in conditions of partial indeterminacy of the outcome is characterized by correspondence between the frequency of actions and the probability...