I was recently reading a PNAS paper entitled “Bringing values and deliberation to science communication” by Thomas Dietz from Michigan State [thanks to Ashley for sending this along]. The basic premise of the article is that robust and useful communication of science is required for that information to be used correctly in making personal decisions as well as formation of policy. I could write a summary of the article, but that has already been done in other places. You should go and read the article yourself rather than relying on summaries that don’t really permit you to gather the entire weight of Dietz’ arguments. In lieu of a true synopsis, I thought it might be interesting to simply provide some key quotes from the article, since it is perhaps one of the most quotable pieces from the peer-reviewed literature I have read in quite some time. The quotes are presented below without commentary, and in the order in which they appear in the article. Some may seem mind-numbingly obvious outside the context of the article, while others may seem incomprehensible. Whatever the case, my hope is that they will pique your interest enough to go and read the article yourself. I should note that there are many threads in the article that hearken to the content of Daniel Kahneman’s Thinking, Fast and Slow, which is fantastic and perhaps should be required reading of all scientists, journalists, and policy makers alike.
Sorry for using this space for off-topic stuff again, but I wanted to take this opportunity to brag about two of my nieces, who are seeing some of their work published. First, a paper from Erica Prochaska’s work at UPenn has appeared in The Journal of Pediatrics. The paper, “Using the Androgen Excess–PCOS Society Criteria to Diagnose Polycystic Ovary Syndrome and the Risk of Metabolic Syndrome in Adolescents” looks at how one can use a variety of criteria to enable early diagnosis of PCOS in adolescents (yes, the title is pretty self-explanatory). If this interests you, I encourage you to check it out.
In a completely different domain, Stephanie Lyon will soon see her paper “Psychotherapy and the Mormon Faith” published in the Journal of Religion and Health. This is a bit far afield for me, and I haven’t seen the pre-print yet, so we will have to wait for it to come out before entering into a deep discussion of the work. Congrats to Steff and Erica!
Add one more niece to the list. Rebecca’s work was recently published in the First Amendment Law Review. Again, pretty far afield for me, so I won’t profess to understand the details of “Faith Healing Exceptions Versus Parens Patriae: Something’s Gotta Give”. Regardless of my limited knowledge of First Amendment Law, congrats to Rebecca are in order!
I thought I would share an interesting presentation by Craig Thompson, President and CEO of the Memorial Sloan Kettering Cancer Center. If you have 30 minutes to spare, it is worth a look. For some time now, we have known that tumors have a much higher glucose demand than healthy tissues. However, this fact rarely translates into dietary advice. The hypothesis is that if tumor needs glucose, then consuming a diet that is low in carbohydrate will effectively starve the tumor and result in necrosis. A diet that contains a higher proportion of calories from fat would in principle be less oncogenic. Thompson acknowledges in the Q&A that current dietary advice would argue against a high fat diet due to the focus on “heart-healthy” diets, but that we need to balance that against the desire to prevent cancer – waiting to treat the disease is clearly not good enough. It is unfortunate that he doesn’t discuss the fact that the demonization of cholesterol and fat is probably misguided. Nonetheless, there are also some interesting ideas out there on using a low carbohydrate dietary strategy to treat advanced cancer, including the work of Eugene Fine and Richard Feinman. You can download a recent paper on the subject here, in which a small (10 patient) sample was studied. You can read Eugene’s discussion of the work on Richard’s blog – it is encouraging to note that even in this very small study, there was a statistically meaningful correlation between disease stabilization (with one case of remission) and dietary ketosis. Getting back to the original point of this post, have a look at Thompson’s presentation (below). Hopefully in the future we can move in a the direction of funding for dietary cancer prevention – there is good reason to believe in this “tumor starvation” approach. Continue reading “cancer – prevention vs. treatment”
I thought I would share a post on climate change that caught my eye:
This showed up in Slate today, and is itself just a short writeup on this post:
It’s been a while since the last post – busy times around here. However, I finally found a few spare moments to read some papers. One that popped out at me is a recent pub in Nature Nanotechnology entitled “Normalization of tumor blood vessels improves the delivery of nanomedicines in a size-dependent manner“. Rakesh Jain from Massachusetts General Hospital is the corresponding author, with contributions from a bunch of other folks, including Moungi Bawendi from MIT. The paper points out one of the main conundrums associated with delivery of therapeutics deep into a solid tumor (regardless of whether they are “nano” or not). Whereas the leaky vasculature, and the associated “enhanced permeability and retention” (EPR) effect can in principle increase the deposition of nanomedicines at the tumor, leaky vessels also lead to an increased interstitial fluid pressure within tumors, which hinders penetration through the tumor. Clearly, poor tumor distribution, and the associated gradients in drug concentration, are not conducive to good clinical outcomes.
However, it has been shown that vascular normalization, which reduces the leakiness of the vessels, can improve clinical outcomes (for traditional chemotherapies) in a number of cancer types, presumably due to better drug delivery and tumor distribution. Jain and co-workers sought to investigate whether this might be true for nanomedicines, which are typically thought to rely upon vascular leakiness for deposition. Would a decrease in the vessel pore size (via normalization with VEGF receptor blocking antibodies) decrease the penetration of nanoparticles?
The basic findings are perhaps not surprising, but are nonetheless very important. Nanoparticles (quantum dots, in this case) around 12-nm in diameter display much better tumor penetration than larger particles (following normalization of the vessels). The authors pointed out that this size is about the smallest that can benefit from the EPR effect, making the absolute particle size an important design consideration in the development of nanomedicines. Larger materials will always suffer from poor vascular escape and tumor penetration, while smaller particles may localize in healthy organs simply by virtue of the size cutoff associated with normal vessels in those organs. In our group, these things are obviously very important, and we are further interested in how particle modulus might change these design rules – hopefully we will have some answers in the near future.
A clever little paper just came out as an Advance Online Publication in Nature Chemistry (Self-reproduction of supramolecular giant vesicles combined with the amplification of encapsulated DNA). Tadashi Sugawara from the University of Tokyo shows in this work that when you fabricate a vesicle containing an amphiphilic imidazolium catalyst, you can actually cause the vesicle to self-replicate when a membrane precursor is placed in solution. Furthermore, the vesicle can be used to encapsulate DNA and PCR reagents, thereby creating self-replicating vesicles that contain replicated DNA. Perhaps the coolest thing about this from a “biosimilar” point of view is that the giant vesicle division is accelerated by the encapsulation of DNA within the vesicle membrane. Thus, only the DNA containing vesicles are actually capable of rapid division and replication. The similarity of this work to actual “synthetic cell” fabrication makes me think that the popular press could have a field day with this…stay tuned.