Brains consist of many cells called neurons: billions of them in a human brain, and hundreds of thousands in the brain of a small fish or a frog tadpole. Many of these neurons are very much alike, and work together to process information in the brain. Yet while they are similar, they are not exactly identical. By looking at how individual neurons within a specific type differ from each other, it is possible to understand more about how they work together.
We have now compared the properties of the neurons in a part of the brain of a developing frog tadpole that processes sensory information. These neurons appear relatively similar to each other in young tadpoles, yet as the tadpoles grow and their brains become more elaborate the neurons become increasingly diverse, and their properties become more unique and nuanced.
Ciarleglio, C. M., Khakhalin, A. S., Wang, A. F., Constantino, A. C., Yip, S. P., & Aizenman, C. D. (2015). Multivariate analysis of electrophysiological diversity of Xenopus visual neurons during development and plasticity. eLife,4, e11351.
A publication by Brooke and Craig Jude in JMBE is focused on building microbial fuel cells (bacterially powered batteries) in the college and local school classroom! These microbial fuel cells serve as lab projects in Brooke Jude’s BIO145 Environmental Microbiology course and are also constructed when local 8th grade classes visit Bard through Center For Civic Engagement (CCE) sponsored events (that are taught by Bard students!)
Citation and full-text link: Jude CD, Jude BA. Powerful Soil: Utilizing Microbial Fuel Cell Construction and Design in an Introductory Biology Course. J Microbiol Biol Educ. 2015 Dec 1;16(2):286-8. doi: 10.1128/jmbe.v16i2.934. eCollection 2015 Dec.
The rise of antibiotic resistance found in microbial pathogens was driven by the use and misuse of antibiotics in modern medicine and agriculture. However, the extent to which antibiotic pollution impacted microbial communities found in soil and remote environments is unclear. Using a metagenomic approach to investigate microbes found in the Canadian high Arctic, Dr. Perron and colleagues found common microbial pathogens resistant to multiple antibiotics among these remote Arctic microbial communities. Dr. Perron’s team also showed that although antibiotic-resistant bacteria were also found in 5,000 years old permafrost soils, these bacteria did not show resistance profiles normally associated with infection.
Citation: Perron GG, Whyte L, Turnbaugh PJ, Goordial J, Hanage WP, Dantas G, & Desai MM. (2015). Functional characterization of bacteria isolated from ancient Arctic soil exposes diverse resistance mechanisms to modern antibiotics. PLoS ONE. 10: e0069533
In this paper a team of neuroscientists from Brown University and Bard College show that Xenopus tadpoles can be used as an experimental model to study molecular mechanisms of autism spectrum disorders (ASD). We used a chemical called valproic acid that is known to increase the incidence of ASD in humans, and studied its action on tadpoles. It turned out that tadpoles exposed to valproic acid developed abnormalities that are surprisingly reminiscent of that in ASD-affected humans. It suggests that tadpoles can indeed be used to study the original molecular reasons that make “autistic brains” develop differently than “normal brains”.
Citation: James EJ, Gu J, Ramirez-Vizcarrondo CM, Hasan M, Truszkowski TL, Tan Y, Oupravanh PM, Khakhalin AS, Aizenman CD. (2015). Valproate-Induced Neurodevelopmental Deficits in Xenopus laevis Tadpoles. The Journal of Neuroscience, 35(7), 3218-3229.
Free text at PubMed Central.
Press-release from Brown University.
In this short article for Science, Felicia Keesing and her colleague Rick Ostfeld synthesize recent research that shows how and why areas with high diversity frequently have lower rates of transmission of infectious diseases of wildlife, humans, and plants. This is particularly compelling because it aligns environmental conservation with public health.
Citation: Keesing, F., & Ostfeld, R. S. (2015). Is biodiversity good for your health?.Science, 349(6245), 235-236.
Full version of the paper can be found at Researchgate.
The spread of antibiotic resistance in human pathogens is one of the most urgent challenges in public health today. While the discovery of new drugs remains central in our fight against microbial infections, our ability to understand how antibiotic resistance evolves in the first place is crucial in the development of sound public health policies. In this Special Issue published in Evolutionary Applications, Dr. Perron, acting as guest-editor, present a collection of articles discussing the different contributions of evolutionary biology and ecology to help solving the current antibiotic crisis.
Web link: http://onlinelibrary.wiley.com/doi/10.1111/eva.2015.8.issue-3/issuetoc
It was known for some time that Xenopus tadpoles try to avoid collisions with objects that approach them, but until now it was not quite clear what part of the brain detects potential collisions and makes the tadpole change its swimming trajectory. In this study Dr. Arseny Khakhalin shows that most likely this calculation happens in the midbrain region called the optic tectum.
Citation: Khakhalin AS, Koren D, Gu J, Xu H, Aizenman CD. (2014). Excitation and inhibition in recurrent networks mediate collision avoidance in Xenopus tadpoles. European Journal of Neuroscience, 40(6), 2948–2962
The ticks that harbor the bacterium that causes Lyme disease can also carry other pathogens. Dr. Felicia Keesing and co-authors showed that ticks are more likely to be coinfected with the organism that causes babesiosis than expected by chance, as ticks are likely to acquire both pathogens when they feed on a single small-mammal host.
Citation: Hersh, Michelle H., Richard S. Ostfeld, Diana J. McHenry, Michael Tibbetts, Jesse L. Brunner, Mary E. Killilea, Kathleen LoGiudice, Kenneth A. Schmidt, and Felicia Keesing. “Co-Infection of blacklegged ticks with Babesia microti and Borrelia burgdorferi is higher than expected and acquired from small mammal hosts.” (2014): e99348.
Download the paper: Hersh et al. 2014 – coinfection