We meet in Branford, CT, about once every 4-6 weeks and topics discussed range from physical sciences, to life sciences and social sciences. A knowledge of the topic being discussed is not required, nor is there any membership requirement or age restriction. Perhaps the only requirement is curiosity and a thirst for knowledge! Science and technology are integral to every aspect of life - history, geography, humanities, music - everything.
Now for a piece of excellent news for Tilde Cafe: as of January 23, 2009 you can find a link to us on the science cafes website maintained by WGBH Educational Foundation - WGBH is the public television station out of Boston, and produces NOVA among many other fantastic shows. Tilde Cafe is the only listed science cafe in CT, and the only one between NYC and Boston!
As of July 2014, the IRS has recognized Tilde Cafe as a 501(c)(3) organization. Gifts are deductible to the full extent allowable under IRS regulations.
© 2009 Deepti Pradhan and Tilde Cafe
April 11, 2015
In the cold light of day - yet another espectacular* Tilde Café afternoon
And once again, our Café afternoon coincided with a wonderful sunny day - there are those who've been suggesting we team up with local meteorologists to bolster their prognostications! The few, the proud, the Tilde Café die-hards, descended on the James Blackstone Library to hear Professor Iwasaki tell us about viruses and managing our relationship with them.
"Microbiome" is a word that Tilde Café attendees will be familiar with, thanks to Paula Kavathas telling us about the human microbiome a little over five years ago, in March 2010 (https://www.youtube.com/watch?v=mmTiUDBBNBk). If you did a PubMed search for published scientific articles that use the phrase "human microbiome", you'd see that until 2010 March there were only 50 articles (the earliest article using this phrase was published in 2002); fast forward to the period between that cafe and today, and that phrase appears in 545 articles published in 5 years. The attention the human microbiome is getting is clearly remarkable. While we have 23,000 genes, this number pales in comparison to the total number of genes (more than 1 million) we carry around with us thanks to the microbes that inhabit us. The NIH Common Fund Human Microbiome Project (HMP) was established in 2008, "with the mission of generating resources that would enable the comprehensive characterization of the human microbiome and analysis of its role in human health and disease." Viral genes, including genes from bacteriophages - viruses that infect bacteria - have been identified as part of human DNA through detailed sequencing efforts across the globe. Because viral replication depends on the host cell it infects, a viral genome (or parts of it) can sometimes remain integrated in the host genome even after an infection. This then propagates and the sequence remains relatively unchanged since the human genome acquires mutations at much slower rates than stand-alone viral genomes. Studying these pieces of stably integrated viral genomes is central to the specialized field of paleovirology. A very brief introduction and review of paleovirology can be found in an article by Aris Katzourakis.
Professor Iwasaki gave us a quick tour through the two arms of the immune system, perhaps one of the most complex parts of our physiology - innate and adaptive immunity, and the manner in which each of these systems propel into action in response to a virus. Innate immunity is the body's first line of defense. Type I interferons, produced at 37 Celsius when a virus infects a cell, play a critical role in quashing a virus via innate immunity - a relatively nonspecific, broad and short-lived response to an attack. Adaptive immunity on the other hand is more complex and longer lived, and can also be conferred via vaccines.
To establish an infection, most viruses need to replicate at 37 Celsius (98.6 F). As recent work from Professor Iwasaki's lab has shown, "most" does not equal "all": the rhinovirus, the perpetrator of the common cold, is able to successfully replicate at the lower temperature (33-35 C or ~91-95 F) in the upper respiratory tract. because the innate immune response cannot be adequately mounted at temperatures below 37 C. While it has been known for some decades that the rhinovirus replicates at these lower temperatures, how it evades the long arm of the immune system has now finally been elucidated by this work. So in winter, keep that nose warm so your cells can make type I interferons to keep you from sniveling!
As a result of years of time and money spent on researching many viral diseases, we now have vaccines for a few of them. Keeping up with vaccination regimens throughout one's life is critical to the health of our species, enhances overall life expectancy, and reduces healthcare costs in the long run. In fact with global mobility on the rise, keeping up with vaccination regimens becomes even more important. Thank you, Professor Iwasaki for a marvelous peek into your research, and showing us that despite a complex and fine tuned physiological system, there are enormous barriers that must be crossed to develop a strategy to overcome viral infections; encapsulating it all in an email is challenging!
Thank you also for your patience in responding to the seemingly innumerable questions from all in attendance. The footage of the afternoon will be posted on the youtube channel later this week.
*We're going to look for superlatives in other languages, since we seem to be running out of them in the English language. Send us your suggestions.
Visit http://www.youtube.com/user/tildecafe for all cafe videos