Center for Behavioral Neuroscience: a prototype multi-institutional collaborative research center

The Center for Behavioral Neuroscience was launched in the fall of 1999 with support from the National Science Foundation, the Georgia Research Alliance, and our eight participating institutions (Georgia State University, Emory University, Georgia Institute of Technology, Morehouse School of Medicine, Clark-Atlanta University, Spelman College, Morehouse College, Morris Brown College). The CBN provides the resources to foster innovative research in behavioral neuroscience, with a specific focus on the neurobiology of social behavior. Center faculty working in collaboratories use diverse model systems from invertebrates to humans to investigate fear, aggression, affiliation, and reproductive behaviors. The addition of new research foci in reward and reinforcement, memory and cognition, and sex differences has expanded the potential for collaborations among Center investigators. Technology core laboratories develop the molecular, cellular, systems, behavioral, and imaging tools essential for investigating how the brain influences complex social behavior and, in turn, how social experience influences brain function. In addition to scientific discovery, a major goal of the CBN is to train the next generation of behavioral neuroscientists and to increase the number of women and under-represented minorities in neuroscience. Educational programs are offered for K-12 students to spark an interest in science. Undergraduate and graduate initiatives encourage students to participate in interdisciplinary and inter-institutional programs, while postdoctoral programs provide a bridge between laboratories and allow the interdisciplinary research and educational ventures to flourish. Finally, the CBN is committed to knowledge transfer, partnering with community organizations to bring neuroscience to the public. This multifaceted approach through research, education, and knowledge transfer will have a major impact on how we study interactions between the brain and behavior, as well as how the public views brain function and neuroscience

Rewarding Properties of Social Defeat

Conditioned place preference (CPP) is a classical conditioning paradigm used to evaluate the rewarding or aversive properties of a stimulus. A stimulus can be an audio, visual, or sensory prompt but can also be stimuli associated with behaviors. Environments associated with sexual and aggressive encounters can become rewarding to both male and female Syrian hamsters regardless of social status. However, we have observed that individually-housed, non-aggressive hamsters find social interaction without aggression or sexual behaviors rewarding. Therefore, we expanded upon our previous experiments using CPP to test the hypothesis that group-housed, male hamsters (n=12) can develop a preference for a negative social experience such as social defeat. The CPP paradigm consisted of an initial preference test (15 min X 2), a conditioning phase (10 min X 5 days), and a final preference test (15 min). The hamster was placed into a CPP apparatus containing two main testing chambers, black and white, connected by a neutral, clear chamber. The pretest was conducted to establish a baseline for comparison to the posttest to determine changes in the amount of time spent in either (black/white) chamber. An individually-housed male (n=11) was paired with a group-housed male in their non-preferred chamber for conditioning. The order of placement in the chambers was alternated daily. Control animals (n=5) were used to evaluate effects of habituation across conditioning trials. The result of our experiment showed that group- housed animals developed a CPP for social defeat. We observed that the preference scores increased from 0.34 (± 0.01) to 0.41 (± 0.04), p = .08 and the difference scores decreased from 243.67 (± 21.72) to 171.25 (± 60.34), p \u3c .05. There were no significant differences between pretest and posttest scores for controls for both preference scores and for difference scores from pretest to posttest. The results of this experiment suggest that that our subjects developed a CPP for social defeat and that their response may have been influenced by the type of social defeat. We believe that an escapable defeat with different aggressors’ parings, as was conducted in our experiment, produced social interaction with novelty but with lower stress levels, leading the animals to develop a CPP for social defeat. The hamster’s reactions to the experiment conducted suggest that their response may have been influenced by the type of social defeat that was experienced. There are two types of social defeat models: inescapable and escapable. An inescapable defeat implies that an animal cannot avoid its aggressor whereas an escapable defeat implies that the animal can. Animals exposed to an inescapable defeat have been found to produce generalized aversion and avoidance towards not only a familiar aggressor but a novel, non-aggressive aggressor with the avoidance greater with the familiar aggressor than the unfamiliar; whereas, animals exposed to an escapable defeat only produce avoidance towards its previous aggressor. However, our previous and current research indicates that all Syrian hamsters regardless of social (aggressive/submissive) and housing (group/individual) status all formed a CPP for social behavior, albeit social aggression or social defeat. Our CPP experiment paradigm, similar to that of an inescapable defeat model in that the animal can avoid its aggressors, perhaps produced a positive CPP for social defeat because the hamsters found the controllability of the defeat with novel aggressors across the conditioning trials to be stimulating. While, the hamsters displayed a CPP for social defeat they were not completely resilient and demonstrated higher vigilance to their surroundings as evidenced by the increased duration in the neutral chamber following social defeat. The hamsters’ behaviors suggest that the conducted experiment produced a combination of mild social defeat with novel interactions that produced less aversion and perhaps lower generalized anxiety which was sufficient to develop a CPP for social defeat

Single nucleotide polymorphisms at the TRAF1/C5 locus are associated with rheumatoid arthritis in a Han Chinese population

<p>Abstract</p> <p>Background</p> <p>Genetic variants in <it>TRAF1C5 </it>and <it>PTPN22 </it>genes have been shown to be significantly associated with arthritis rheumatoid in Caucasian populations. This study investigated the association between single nucleotide polymorphisms (SNPs) in <it>TRAF1/C5 </it>and <it>PTPN22 </it>genes and rheumatoid arthritis (RA) in a Han Chinese population. We genotyped SNPs rs3761847 and rs7021206 at the <it>TRAF1/C5 </it>locus and rs2476601 SNP in the <it>PTPN22 </it>gene in a Han Chinese cohort composed of 576 patients with RA and 689 controls. The concentrations of anti-cyclic citrullinated peptide antibodies (CCP) and rheumatoid factor (RF) were determined for all affected patients. The difference between the cases and the controls was compared using <it>χ</it>²analysis.</p> <p>Results</p> <p>Significant differences in SNPs rs3761847 and rs7021206 at <it>TRAF1/C5 </it>were observed between the case and control groups in this cohort; the allelic p-value was 0.0018 with an odds ratio of 1.28 for rs3761847 and 0.005 with an odds ratio of 1.27 for rs7021206. This significant association between rs3761847 and RA was independent of the concentrations of anti-CCP and RF. No polymorphism of rs2476601 was observed in this cohort.</p> <p>Conclusions</p> <p>We first demonstrated that genetic variants at the <it>TRAF1/C5 </it>locus are significantly associated with RA in Han Chinese, suggesting that <it>TRAF1/C5 </it>may play a role in the development of RA in this population, which expands the pathogenesis role of <it>TRAF1/C5 </it>in a different ethnicity.</p

The Polygenic and Monogenic Basis of Blood Traits and Diseases

Blood cells play essential roles in human health, underpinning physiological processes such as immunity, oxygen transport, and clotting, which when perturbed cause a significant global health burden. Here we integrate data from UK Biobank and a large-scale international collaborative effort, including data for 563,085 European ancestry participants, and discover 5,106 new genetic variants independently associated with 29 blood cell phenotypes covering a range of variation impacting hematopoiesis. We holistically characterize the genetic architecture of hematopoiesis, assess the relevance of the omnigenic model to blood cell phenotypes, delineate relevant hematopoietic cell states influenced by regulatory genetic variants and gene networks, identify novel splice-altering variants mediating the associations, and assess the polygenic prediction potential for blood traits and clinical disorders at the interface of complex and Mendelian genetics. These results show the power of large-scale blood cell trait GWAS to interrogate clinically meaningful variants across a wide allelic spectrum of human variation. Analysis of blood cell traits in the UK Biobank and other cohorts illuminates the full genetic architecture of hematopoietic phenotypes, with evidence supporting the omnigenic model for complex traits and linking polygenic burden with monogenic blood diseases

Planetary Rings

Planetary rings are the only nearby astrophysical disks, and the only disks that have been investigated by spacecraft. Although there are significant differences between rings and other disks, chiefly the large planet/ring mass ratio that greatly enhances the flatness of rings (aspect ratios as small as 1e-7), understanding of disks in general can be enhanced by understanding the dynamical processes observed at close-range and in real-time in planetary rings. We review the known ring systems of the four giant planets, as well as the prospects for ring systems yet to be discovered. We then review planetary rings by type. The main rings of Saturn comprise our system's only dense broad disk and host many phenomena of general application to disks including spiral waves, gap formation, self-gravity wakes, viscous overstability and normal modes, impact clouds, and orbital evolution of embedded moons. Dense narrow rings are the primary natural laboratory for understanding shepherding and self-stability. Narrow dusty rings, likely generated by embedded source bodies, are surprisingly found to sport azimuthally-confined arcs. Finally, every known ring system includes a substantial component of diffuse dusty rings. Planetary rings have shown themselves to be useful as detectors of planetary processes around them, including the planetary magnetic field and interplanetary impactors as well as the gravity of nearby perturbing moons. Experimental rings science has made great progress in recent decades, especially numerical simulations of self-gravity wakes and other processes but also laboratory investigations of coefficient of restitution and spectroscopic ground truth. The age of self-sustained ring systems is a matter of debate; formation scenarios are most plausible in the context of the early solar system, while signs of youthfulness indicate at least that rings have never been static phenomena.Comment: 82 pages, 34 figures. Final revision of general review to be published in "Planets, Stars and Stellar Systems", P. Kalas and L. French (eds.), Springer (http://refworks.springer.com/sss