The relationship between scientists and the broader public is not always an easy one; many outside the field view science as somewhat unapproachable, while researchers are generally not trained to communicate their work to non-scientists and may find such activities prohibitively time consuming. Addressing these issues in a recent manifesto aimed directly at investigators, neuroscientist and author David Eagleman gives a compelling argument as to why scientists should strive for greater public dissemination of their work.
While acknowledging the challenges of sharing research with the public, Eagleman provides a systematic series of reasons why doing so is nonetheless worthwhile and important. Some of Eagleman’s reasons focus on Continue reading “Spreading the Wealth: The Importance, and Challenge, of Disseminating Science”
My favorite tweets from the recent #sciconfessions hashtag party. Continue reading “Confessions on the Science Floor”
Taking vitamin supplements might not be as healthy as you think
Antioxidant vitamins, like vitamin C and E, are thought to boost health by reducing the creation of DNA-damaging free radicals that can contribute to the ageing process. In lab mice, there is some suggestion that vitamin supplements can extend lifespan, but since laboratory-bred mice are genetic clones, such studies may bear little relevance to a hugely genetically diverse human population.
Giving wild animals, such as the short-tailed field vole, either vitamin C or E supplements has now been shown to have a less positive impact on health. Continue reading “A Marvelous Month of Science”
Let me begin this blog entry by first apologizing to those of you who had hoped to maybe learn another snippet of cancer biology or read a summary of a couple interesting scientific papers. Instead, this week’s entry is going to be more a reflection of my graduate career. Forewarning, I think my brain is still recovering from the intense past few weeks so I can only hope that my thoughts seem somewhat connected.
I have to confess, this decision is totally influenced by the fact that I just defended my thesis two days ago and I had the opportunity to interact with students still in their first couple of years of graduate school while attending a conference last weekend. The conversation I had with these students got me thinking about the roller-coaster ride that is graduate school. We all agreed that Continue reading “Through The Looking Glass”
Scientists and philosophers alike have long puzzled over how we perceive time; is there a central “clock” mechanism somewhere in the brain? Or is time sensed in association with particular sensory stimuli? Neuroscience has demonstrated that temporal information can be encoded in specific sensory cortices. This week in the Journal of Neuroscience Salvioni et al. show that two particular areas of human visual cortex, V1 and V5, play a causal role in temporal perception and begun to clarify how these regions function in specific stages of processing temporal information.
The authors asked participants to determine which of two intervals, each flanked by flashes of light, Continue reading “It’s About Time and You Know It!”
The brain contains a vast diversity of cell types differing in genetic composition, structure, output targets, and other attributes, and the specialized functions of these many classes remains a central question in the field. Recent research by Runyan and Sur helps address the specific question of how a neuron’s shape relates to its activity and role in a circuit by demonstrating a direct correlation between dendritic morphology and activity pattern in a particular interneuron class.
Runyan and Sur labeled interneurons containing the calcium binding protein parvalbumin, so called PV cells, in the primary visual cortex of mice with red Continue reading “It Takes All Kinds”
Down syndrome is caused by the most common chromosomal abnormality in live-born humans: Trisomy 21. Individuals with Down syndrome have three copies (trisomy) of chromosome 21 instead of the usual two. This excess of genetic information leads to deviations in embryonic development such that the baby is born with a subset of defects from a spectrum of characteristic traits. The most obvious indicators are the distinctive Down syndrome facial features (almond shaped eyes, small ears, large tongue) and abnormalities of the hands (single crease on palm, small curved pinky fingers). Further examination may then reveal more serious medical problems including heart abnormalities, gastrointestinal defects, and impaired vision and hearing. Intellectual disabilities are also a common problem. Continue reading “Chromosome Silencing Offers New Insights into Down Syndrome”
Microorganisms are the most abundant and diverse cellular life forms on the planet. Unfortunately though, we have only been able to culture a small subset of microbial species in the laboratory. These represent just a tiny fraction of the environmental diversity. Furthermore, we have only been able to sequence the genomes of organisms that we can culture. Our knowledge of microorganisms is therefore highly biased towards cultivated bacteria and archaea that almost certainly do not represent the full environmental diversity.
Research published two weeks ago in Nature by a team led by Tanja Woyke from the DOE Joint Genome Institute in California has attempted to address this issue. The researchers used an emerging technique Continue reading “Shining Light on Microbial Dark Matter”
I’ve often wondered why humans are so bad at reproduction. It’s been estimated that 10-30% of all fertilized eggs are aneuploid, and approximately one third of all miscarriages are due to aneuploidy (Hassold et al.). In striking contrast, only 1-2% of fertilized eggs are aneuploid in mice. As a researcher that studies meiosis, this baffles me. The meiotic program is astoundingly complex, coordinating the repair of programmed DNA damage, finding and pairing homologous chromosomes, along with attaching the spindle in the correct orientation. This complexity requires multiple checkpoints throughout the process to ensure everything is going as planned; if something goes wrong, the checkpoint stops the cell. Given multiple opportunities to ensure chromosomes are properly segregated, how is it that, in humans, aneuploid cells not only make it through a complete meiosis, but also go on to complete oogenesis?
Recent work from Dokshin et al. suggests that one potential way this can happen is to decouple oogenesis from meiosis. In mice, early germ line cells initiate meiosis after Stra8 expression is turned on by a retinoic acid signal. In the absence of Stra8, cells never initiate meiosis, and by 6-8 weeks of age, the ovaries contain no germ cells. However, a very small percentage of cells are able to escape the Stra8 phenotype, and while they still don’t initiate meiosis, they do proceed through oogenesis. These “oocyte-like cells”, as the authors call them, have the same morphological and physiological characteristics as normal oocytes: they are able to make a zona pellucida, generate follicles, can be ovulated and fertilized, and the embryo can undergo the first division. When the authors looked at the chromosome complement of the oocyte-like cells, they found that the chromosomes were randomly distributed between the polar body and the oocyte-like cell.
Certainly, these data show that in the absence of meiosis, the vast majority of female germ cells will not differentiate; therefore, there must be some way of monitoring the meiotic state of a cell before oocyte differentiation begins. However, this monitoring clearly can fail, as the Stra8 deficient mice do produce oocyte-like cells capable of being fertilized. The authors suggest some cases of human infertility may be explained by a disconnect between oocyte differentiation and meiosis. It will be fascinating to compare the mechanism of communication between meiotic state and oocyte differentiation in humans to other organisms, and determine if the apparently higher rate of aneuploidy in humans is sometimes due to miscommunication.
Training new scientists is a critical aspect of scientific progress, Pereda, Schweizer, and Zottoli argue in a recent Neuron article , and deserves careful consideration now more than ever. The authors use the Grass Laboratory, a program in which post doctoral fellows and advanced graduate students undertake independent projects for a summer, as an example to explore current issues in new investigators’ education. The strength of the Grass Laboratory, the authors suggest, is the emphasis on fostering a highly creative, passionate approach to research and the confidence to pursue such work. This is particularly important in the current climate of research. Pereda et al. point out that over the past decade research has increasingly been driven by profitability; the realization that science and technology could garner economic strength has lead funding agencies in many nations to reward research with specific Continue reading “How To Train Your Scientist”