Courtesy sirgabeThere’s something I want to get out of the way straight off the bat: the original title for this post was “Monday Nutrition Extravaganza: Chemicals in your food, playing with your manhood!” And while that has a certain whimsical charm, a re-read revealed hidden, disturbing meaning in those words. And I didn’t want to subject you Buzzketeers to that. I just thought you should know.
So, moving on, what’s this stuff playing with our manhood, now?
Chemicalz in our foodz! And stuff.
Earlier today, I came across this study about how there seems to be a correlation between high levels of chemicals call phthalates in pregnant mothers’ urine, and a lowered incidence of “masculine play” in their male children. (“Girls’ play behavior” didn’t seem to be affected.)
Phthalates are a group of chemicals added to plastics to make them softer and more pliable. We all like soft plastic—no one is arguing that!—but phthalates are all over the place, and increased exposure to them (all sorts of products and packaging use phthalates) is raising concerns about how those chemicals affect us, particularly during childhood development. See, phthalates are antiandrogens, meaning that they mess with the way your body works with hormones like testosterone. Testosterone plays an important role in how we physically develop, and perhaps in how we act. The boys whose mothers had higher levels of a couple kinds of phthalates demonstrated less “male-typical” behavior. The study looked a preferred toy types (trucks versus dolls), activities (“rough-and-tumble play”), and “child characteristics.”
Now, these are slightly sticky things to go judging kids on. Some folks might argue that these characteristics aren’t linked to biology so much as social conditioning. And it feels a little weird quantifying characteristics in children (and, let’s be honest here, characteristics which may not have a solidly identified “norm,” but nonetheless have all sorts of social and sexual baggage that we are uncomfortable with and often deal with in the worst ways). However, there does seem to be some statistical association here, whatever the causal relationship is. One hypothesis is that phthalates alter fetal production of testosterone at an important period of development, affecting “brain sexual differentiation.” It’s not so hard to imagine—a year ago I did a post on how certain common chemicals in pregnant mothers seemed to be causing penis deformities in their male children. The culprit there? Phthalates. The women in that story, however, had had exceptionally high exposure to phthalates (their jobs had them in constant contact with phthalate-containing hairspray), so it’s probably not something to lose sleep over, but it’s worth knowing.
And while phthalates aren’t supposed to be in food packaging, the next article I came across (this is an extravaganza, after all) deals with another plastic additive, BPA, that is found in food packaging, and which may also cause some hormone-related havoc.
BPA has come up on Science Buzz before. It’s in all sorts of packaging and bottles (it’s the reason your over protective mother doesn’t want you to use nalgene bottles) and it may affect tissue development, potentially increasing cancer risks.
We don’t care about that, though, right? Sure, cancer is out there, but in the future, not right now, you know? I know. But BPA’s latest appearance in the news may bring some immediacy to the concern over its use. Concern for some people. For men, I mean.
Chemical BPA in workers related to sex problems, says the Washington Post. “Sex problems”? We don’t want those! Chinese men working in a factory that uses BPA were found to have high rates of sexual problems. (I won’t be defining what “sexual problems” are because whatever you just imagined was probably correct.) Now, these guys have BPA levels about 50 times higher than the average American. But, still, something like 90% of Americans have detectable levels of BPA in their urine. Again, probably nothing to lose a lot of sleep over, but something worth knowing about. This professor is of the opinion that BPAs should be banned, even though most of us will probably never be exposed to dangerous levels of it, because a) it’s not a natural part of our diet; b) it’s not actually necessary in plastics processing; c) it accumulates in the body, and we still don’t know what level at which it begins to become harmful (ask those Chinese guys); and d) it’d be relatively easy to get it out of the food and water supply, unlike some other potentially harmful chemicals.
Accepting that scientific studies are necessarily very focused to eliminate variables, both of these stories still left me wondering what affect phthalates and BPAs have on women and girls. On one hand, one tries to avoid the mindset that average human physiology=male physiology, but on the other hand it’s usually just males that have penises, making their medical problems a little more hilarious.
There are so many… things out there, and they’re all doing… stuff! Interesting to know.
Courtesy Jiju Kurian Punnoose
In the embryo, the pancreas and liver tissue develop from the same family of cells. Crucial for the creation of the pancreas in the embryo, is the Pdx-1 gene.
By infecting adult human liver cells with a harmless virus engineered to carry Pdx-1, the liver cells began produced Pdx-1 protein.
Sarah Ferber and her colleagues at the Sheba Medical Center in Tel Hashomer, Israel, showed that the gene deactivates a range of genes relevant to the cell's function in the liver, as well as activating unexpressed genes vital for beta cell function (beta cells produce insulin).
The ultimate plan is to take liver cells from people with diabetes, reprogram the cells and reinject them. Because they are the patient's own, the cells should escape rejection by the immune system, sparing the individual a lifetime of daily insulin injections. "Potentially, patients can be donors of their own therapeutic tissue," says Ferber. New Scientist
Ferber is presenting the work on July 9 at an International Society for Stem Cell Research (ISSCR) meeting in Barcelona, Spain.
Courtesy USDALets say you are walking in the woods and you see a 12 point deer ahead of you. You sneek up quietly but not quietly enough. The deer hears you looks right at you and begins to charge. Before you know it its right antler has sheered off your arm! What do you do? Well if you were a salamander you would simple re-grow it.
For centuries scientist have wondered how salamanders regenerate limbs. In recent history they believed the tissue around the injury regressed into pluripotent stem cells (the kind we have all heard about that can morph into many different types of cells) and they reform into each cell type needed to create the limb.
This research was conducted to help understand how the salamander was able to do this amazing feat so that we could apply it to humans. Unfortunately, stem cells are not the easiest thing to work with but, that is old news now.
New research has shown that the salamander's cells do not regress but have memory that allows them to grow into what they once were. The memory is so good that the cartilage from the lower limb re-grows in the lower limb again.
The way scientist were able to do this was by engineering a florescent protein in a group of salamanders and transplanted only a select cells (skin, bone, muscle, etc) into embryos. After the embryos had grown, a limb was amputated. When it re-grew scientists observed that the glowing cells were not spread out amongst all the different cell types, as it would be if the cells had regressed into blank slates, but the florescent protein was only found in the original transplanted cell type.
Good new for us humans. This new finding may, although most likely not in our life time, make it easier to regenerate human organs.
Courtesy Apollo13Ma (background photo), public domain and Mark RyanA study out of New Zealand says a warmer climate speeds up molecular evolution in mammals. The concept isn’t exactly a new one. Scientists have known that a warmer environment increases the pace of microevolution for other types of life, such as some plants and marine animals, but evidence that it affects mammals – which are warm-blooded (meaning their temperature is regulated internally) – has not been observed before.
Lead researcher, Len Gillman from Auckland University of Technology, said the result of the study was “unexpected”.
""We have previously found a similar result for plant species and other groups have seen it in marine animals. But since these are 'ectotherms' - their body temperature is controlled directly by the environment - everyone assumed that the effect was caused by climate altering their metabolic rate.""
Since DNA can potentially mutate each time a cell divides into two copies of itself, the faster (and more often) these divisions take place, the more chances advantageous mutations will be passed onto subsequent generations, and the faster microevolution takes place.
Gillman and his crew traced and compared small genetic changes in 130 pairs of related species that lived in different latitudes, focusing on a single gene in each pair. They then compared the gene against that of a common ancestor, and were able to determine which of the two mammals’ DNA had mutated (microevolved) more rapidly. The changes were small-scale, but the species living in the more tropical environment showed a faster pace in its level of molecular evolution.
The results of the study appear in Proceedings of the Royal Society B.
Wait, you say, fractionally raising your heads from your overstuffed couches and baths full of tepid water. Didn’t John Snow actually die in June? And, like, didn’t he die on June 16, not on the 17th?
Well, yes, June 16, 1858, was in fact the day John Snow died. But I only just made up Snow day, and I wasn’t paying attention yesterday. Plus, do y’all even know who John Snow was?
Oh, John Snow was the most marvelous man! He drugged queen Victoria! He deprived thirsty communities of pump handles! He saved London from tiny invisible monsters! Oh, what a man!
John Snow was the sort of guy that posthumously gets the Cleverboots Award for Correct Thinking. Sort of like how I will surely be recognized with a Cleverboots Award years after I die, for how strikingly accurate my public ranting on the subjects of invisible lasers, lizard people, and “stay away from me, wizards!” will prove to be.
Snow was one of the first people to study the used of ether and chloroform as anesthetics. Which is to say, people had used those compounds as anesthesia before, but Snow calculated doses that would leave you somewhere between horrible pain and drugged to death. That was important. Everybody’s favorite queen of England (Victoria, duh) had Snow personally administer her anesthesia during the births of her eighth and ninth children. Once people saw Victoria doing it, everybody wanted in on anesthesia.
Snow’s greatest achievement, perhaps, came in an episode I like to call “Johnny Snow vs. Cholera.”
See, in the middle of 19th century in London, people were sort of split into three groups. There was the “Cholera is caused by poisonous gases” group. Most everybody thought that theory was the best, and it was called the “miasma theory.” There was also the “Cholera is caused by something tiny or invisible in water” group. This was pretty much what we call “germ theory,” and most everybody was all, “Germs? That’s stupid. Check your head!” And, finally, there was the “Hey, we’re actually dying of cholera over here” group, and most everybody thought they were gross.
But not John Snow! Instead of arguing and making up theories based on what seemed reasonable, he actually went out and looked at stuff. Gasp!
Without knowing for certain exactly how cholera was being transmitted (germs or miasma, or whatever), Snow began to record who in London was getting the disease, and he plotted cases on city street maps. He saw clusters of the disease in certain areas of the map, and so he looked for common elements. In the case of one outbreak, Snow realized that the majority of infected people were getting their water from one of two water companies, both of which were pulling water from a dirty (read: full of sewage) section of the Thames river. In another outbreak, Snow found that most of the victims of the disease were getting their water from a particular public pump. When John Snow had the handle of the pump removed, so that nobody could get water from anymore, the outbreak ended.
Snow’s discoveries from studying the cholera outbreaks added to the evidence for germ theory, and, perhaps more importantly, constituted a huge stride forward in the science of epidemiology. Snow wasn’t just figuring out how to cure diseases, he was tracking down where they start, and learning about how they move through populations. These are the same basic principles behind the actions health organizations still take today when dealing with outbreaks in the much larger population pools (or pool) of the 21st century.
It’s pretty interesting stuff. Check out this Snow-stravaganza: UCLA’s comprehensive page on John Snow and the cholera outbreaks.
Now enjoy what’s left of your Snow day.
Stem cells are the body's master cells, able to morph into any type of tissue, organ, or blood. Patient specific stem cells hold the promise of reversing cancer, diabetes, Alzheimer's and other diseases and also allow researchers to grow patient-specific organ and tissue transplants which will not require harmful anti-rejection drugs.
Up until now, the stem cells produced from a patients own skin had within them remnants which made them unsafe (linked to health problems such as genetic disorders and cancer).
Robert Lanza and a team led by Kwang Soo Kim of Harvard University succeeded in delivering the genes by fusing them with a cell penetrating peptide which does not pose the risk of genetic mutation. Their findings are published in the journal Cell Stem Cell.
This system eliminates the potential risks associated with the use of viruses, DNA transfection, and potentially harmful chemicals and in the future could potentially provide a safe source of patient-specific cells for regenerative medicine. Cell Stem Cell
Their technique involves soaking cells in human proteins that turn back the clock biologically, making the cells behave like powerful embryonic stem cells. They plan to seek Food and Drug Administration permission to test the cells in people by next year.
"This method eliminates the risks associated with genetic and chemical manipulation, and provides for the first time a potentially safe source of iPS cells for translation into the clinic," Lanza said.
"This is the ultimate stem cell solution -- you just add some proteins to a few skin cells and voila! Patient-specific stem cells!" Reuters
Only a tiny percentage of skin cells in the study transformed into iPS cells over two months (0.001%).
"How readily or quickly this technology is applied, and whether the efficiency is improved, are things that we will have to wait and see. said Dr. Arnold Kriegstein, director of the Institute for Regeneration Medicine at the University of California" Time
So, let’s see… if we’re arranging the list in terms of the order in which I’ve realized each one, then this new development falls at the end, right after “better resistance to sunburn” and “less likely to get testicular cancer.”
If the list is alphabetical (how nice and neat!), it goes between “more powerful backstroke” and “more powerful interpersonal skills.”
Despite my rabbit-killing-strength grip and my powerful stammer (each unlikely to be beaten by women as a whole), the bite of each item on the list burns like jalapeño scorpion stings.
It’s nice, then, that this new fact isn’t quite so painful to accept. See, I like getting sick. I want to get sick. In particular, I want to get the swine flu. My great-grandfather was beaten (i.e. killed) by the swine flu back in 1920 or so, and I’ve been aching for a rematch. Swine Flu vs. JGordon Round II: The Final Showdown: This Time it’s Personal: A Century-Old Family Feud Comes to Blows: To the Death!
Sure, I don’t actually want to die at all, but this disease needs to at least get a foothold in my system if we’re finally going to see who’s the bigger man. (Me, duh.)
If I were what we often call a “lady,” my powerful immune system would make the flu showdown less likely. So thank goodness that that’s not the case. My female body would be producing estrogen left and right, and that estrogen would be blocking the production of an enzyme called Caspase-12. Caspase-12, precious Caspase-12, is needed in my body, because it blocks my inflammatory processes. Inflammation is one of the body’s primary defenses against infection. Blood flow increases at the site of an injury or infection during inflammation, beginning the healing process and delivering structures that kill and absorb pathogens. And I don’t want that. I mean, if every time Evander Holyfield approached Mike Tyson’s boxing ring a flood of blood and plasma crushed Holyfield and washed him away, how would The Dynamite Kid ever have gotten the chance to prove who’s tougher? I want to let the swine flu into my ring, and then I want to bite its ear off and threaten to eat its children.
I’m leaving it up to my frail male body to arrange this fight.
Courtesy Opabinia regalis Understanding proteins and how they work is very useful. One type of protein called an enzyme is like a nano sized factory that can take apart molecules or build new molecules out of smaller parts.
Plant cellulose can be turned into ethanol fuel. Oil slicks could be digested into non-pollutants. Custom designed proteins will soon allow "living" factories that can manufacture almost anything we can imagine. Protein "hackers" are creating synthetic antibodies — proteins designed to bind tightly to specific targets, such as tumor cells, which can then be destroyed.
To accomplish this goal, DARPA is investing in the development of new tools in diverse areas such as topology, optimization, the calculation of ab initio potentials, synthetic chemistry, and informatics leading to the ability to design proteins to order. At the conclusion of this program, researchers expect to be able to design a new complex protein, within 24 hours, that will inactivate a pathogenic organism. Protein Design Processes (DARPA)
Proteins are made from a complex chain of amino acids. Several resources are helping to illuminate the complex relationship between the sequence of a chain of amino acids, the shape into which that chain will ultimately fold, and the function executed by the resulting protein.
The Protein Data Bank is an ever growing data bank of detailed schematic protein information. Another program that is helping to understand how proteins are shaped is the Rosetta@Home project which allows thousands of home computers to determine the 3-dimensional shapes of proteins being designed by researchers.
"Would you like to play a new computer game and help scientists analyze protein chemistry -- at the same time? Here is a fun and interesting computer puzzle game that is designed to fold proteins -- the objective is to correctly fold a protein into the smallest possible space." Grrlscientist
Watch this video to learn how to "fold-it"
What if your doctor could prescribe a pill that would erase any and all of your worst memories instantly?!
Rather than reliving it every single day, you could simply forget the time in 6th grade when you farted while doing sit-ups in gym class, and the day that your beloved cat Pookie was run down by your mother's Buick, and the boyfriend who broke your heart when he ran off to join the circus.
Rather than dwelling on bad memories, you could forget about them and move on to live the rest of your happy sunshiny life.
While it may sound like the plot of a certain indie film, brain scientists at a lab in Brooklyn are working on a scientific breakthrough that may make all of this possible. They've discovered that a chemical in the brain called PKMzeta acts like a speed dial to all of our worst (and best) memories. When a drug called ZIP is injected directly into the brain, memories are blocked and viola! No more dwelling on the painful, embarrassing, traumatic past.
Nevermind that it isn't quite that simple, or that this method has only been tested on rats, or that it involves a chemical being injected directly into the brain. It's from Brooklyn, so you know it'll be on the gifts & novelties table at Urban Outfitters just in time for the holidays. In fact, I can already see the marketing campaign involving lots of waifish models who apparently forgot to eat.
While this kind of 'made to order' miracle memory eraser won't be hitting the shelves anytime soon, there is a whole lot of money being spent on research that aims to better understand how memory works inside our brains. The reason that scientists want to know how memory works is that memory is so important to our emotions, our ability to learn, our spatial knowledge, our motor skills and much much more. When it isn't working as it should be, all kinds of problems can result.
For some people, painful and traumatic memories can wreak havoc on their emotional and social lives. Post-Traumatic Stress Disorder and Depression are examples of diseases that involve the unconscious recall of frightening or upsetting memories. If these memories could be blocked, patients might experience a dramatically improved quality of life. Bad habits are also tied to our memories, since addictive behaviors are learned. If memories of experiences with drugs and alcohol could be blocked, some addicts might stand a better chance of recovery. And for those who suffer from Alzheimer's or Dementia, improvements in the understanding of memory could lead to new methods of memory enhancement, helping to reduce the impact of these diseases.
While plenty of good things will come from this kind of research, it also raises ethical questions. Any drug that can dramatically improve or block selected parts of our memory will inevitably find a commercial market among people who may not suffer from any disease at all. Students who can afford them might start taking memory enhancing drugs right before an exam, criminals might use memory blockers to short circuit the moral questions that arise from their behavior and ordinary people might be tempted to use memory blockers to forget painful or embarrassing moments, rather than learning from them.
To top it all off, since our good and bad memories are not neatly sorted for doctors to target, erasing painful memories would probably mean getting rid of some of the good ones as well. Sometimes it's hard to tell which is which, since good or bad, your memories make you who you are today.
Source: New York Times
Courtesy Mike Jones
Embryonic stem (ES) cells are like blank cells that give rise to every type of cell and tissue in the body.
In Nov., 2007, scientists reprogrammed human skin into stem cells. That technique used cancer causing viruses which remained in the created stem cells.
Such genetic baggage posed safety concerns for potential therapies like cell transplants, and confounded work in the lab, as the introduced genes sometimes spurred mutations that interfered with the normal function of induced cells.
Now, by using a plasmid rather than a virus, James Thompson and Junying Yu have converted adult skin cells into pluripotent stems cells that are completely free of vector and transgene sequences.
The resulting cells, says Thomson, are remarkably similar to embryonic stem cells and show the same capacity to proliferate indefinitely in culture and diversify into all the cell types of the human body. Univ of Wisconsin News
This is a major advance toward safely reprogramming cells for clinical use. The new viral vector-free iPS cells will be available to researchers almost immediately through the International Stem Cell Bank at the WiCell Research Institute.
Research paper abstract in Science:
Human Induced Pluripotent Stem Cells Free of Vector and Transgene Sequences