maradydd: (Default)
First, the OMGWTFBBQ. Via Pharyngula, the Hastings Center Bioethics Forum, and TIME Magazine: pediatric endocrinologists Maria New and Saroj Nimkarn are advocating prenatal treatment with the glucocorticoid dexamethasone to "reduce behavioral masculinization" of female children.

Yes, you read that right: they want to expose pregnant mothers to one of the most potent, adverse-effect-prone steroids out there in the hopes of molding unborn girls into models of femininity.

I'll give you a few minutes to find where your lower jaw rolled off to and get a glass of water -- throwing up in your mouth a little is bad for your teeth. When you get back, I'll expand a little on the current standards of practice, and then we're going to go over some organic chemistry.

Back now? Great. First, PZ got one important fact wrong: the American Academy of Pediatrics and other noteworthy medical organizations have absolutely not condoned or endorsed this practice. The "consensus" to which PZ refers is an agreement that the study of dexamethasone as a preventative for congenital adrenal hyperplasia due to 21-hydroxylase deficiency should be conducted "via IRB-approved clinical trials through research centers large enough to obtain meaningful data" and with follow-up studies. This is, in my opinion, a reasonable position. CAH gets press because one of its effects can be ambiguous genitalia, sometimes aka "intersex", but its effects on aldosterone (one of the steroids your body produces) can lead to dehydration, hyponatremia, hyperkalemia, metabolic acidosis and death, in infancy. "Ambiguous" is also used, erm, ambiguously; it doesn't only mean "large clitoris", it also includes things like the urethra and vagina opening into a common cavity and causing severe urinary tract problems.

If there is sufficient reason to believe that prenatal dexamethasone can keep children whose genes prevent them from producing 21-hydroxylase alive, or make it possible for them to avoid difficult, expensive and painful surgery to restore urinary function, that is a valid avenue for research conducted under the auspices of an institutional review board. Attempting to tweak girls' personalities to make them more girly is way, way out of bounds, and New and Nimkarn should be censured for even suggesting the idea.

But what I really want to talk about is steroids, and what you, dear reader, do and don't already know about them.

"Steroid" is a really, really broad term. It's as broad as "sugar" or "alcohol". (The categories also overlap, which can be confusing; there are sugar alcohols and steroid alcohols.) When you think of "sugar" you probably think of that grainy white stuff you put in your coffee, and when you think of alcohol you probably think of booze -- but the picture is actually much bigger. All monosaccharides and disaccharides are sugars, including the ribose and deoxyribose that form the backbone of your RNA and DNA. Ethanol is the alcohol we drink, but it's just one of the aliphatic alcohols, which also include isopropanol (rubbing alcohol), methanol (can blind or kill you if you drink it!), xylitol (used to sweeten chewing gum), mannitol (baby laxative), ethylene glycol (antifreeze!), and glycerol (aka glycerin). I won't bore you with all the various non-aliphatic alcohol families, but there are a lot of them. So, also, with steroids.

Steroids are emphatically not just what dumb jocks inject to get really ripped really fast. (Those are certain anabolic steroids.) Just as "alcohol" refers to organic molecules with an -OH bound to a carbon atom and "sugar" refers to a particular type of carbohydrate building block, "steroid" specifically means "molecule with three six-carbon rings and one five-carbon ring in a particular arrangement". (That four-ring core is called a sterane, if you were curious.) And, wow, are there ever a lot of them. Cholesterol is a steroid. So are androgens (including testosterone), estrogens (there's more than one), and progestagens (humans only have the one, progesterone). But unless you're on hormonal birth control, taking estrogen or testosterone replacements, taking progesterone as part of fertility treatment, or otherwise tweaking your own sex hormones, if your doctor prescribes you a "steroid" it is almost certainly going to be one of the corticosteroids.

Dexamethasone is, as I said above, a glucocorticoid -- a member of the family of corticosteroids that can affect immune function. (In the interest of space, I'm going to skip the other family, the mineralocorticoids.) It is, not to put too fine a point on it, the nuclear option of corticosteroids. Long-term use -- which, for glucocorticoids, means more than a week -- causes the adrenal glands to start shutting down; stopping glucocorticoids abruptly after this has happened can cause an Addisonian crisis, which can be fatal. Even long-term use as directed frequently causes Cushing's syndrome, which has a whole raft of nasty symptoms including rapid weight gain, high blood pressure, insulin resistance, severe anxiety, and psychosis. As if that weren't enough already, long-term use also causes osteopenia, a lowering of bone density that is the precursor to osteoporosis.

Given the degree of side effects involved with long-term dexamethasone usage -- and the several weeks of treatment involved in the New and Nimkarn study constitutes "long-term" -- the "behavioral masculinization" paper rolls over from "horrible" to "sheer, unrestrained evil". They are literally advocating putting pregnant women through multiple weeks of chemical torture -- not to save lives, but in pursuit of a behavioral "ideal".

If you think this is anything even remotely resembling right, I invite you to spend a month on dexamethasone -- without medication to mitigate side effects, remember we can't give benzos to pregnant mothers because they might adversely affect the fetus! -- and find out what it does to you. The stretch marks alone -- which look more like "I lost a fight with a cage full of tigers" than "boo, cellulite" -- will last a lifetime; the psychological damage from finding out just how deep your capacity for violence and self-hatred can run may fade, eventually.

All that said, there is one extremely valid prenatal use for dexamethasone. If you're about to give birth to a premature baby younger than 34 weeks, one injection of dexamethasone 24-48 hours prior to birth will help the baby's lungs produce the surfactant which it needs to be able to breathe. (Multiple doses used to be the standard, but -- big surprise -- it turns out that the beneficial effects of multiple doses are no higher, in any statistically significant sense, than of a single dose, and the adverse effects on both mother and fetus with multiple doses are worse.) Consider the difference, though: one injection versus several weeks of dosing, sharp increase in likelihood of survival versus reinforcing social norms. It's like day and night.

What it all comes down to, in the end, is this: be an informed patient. Ask questions. When you're prescribed a medication, the minimum you need to know is:
  1. What exact medication is this? Don't accept a category as an answer. You wouldn't hire a contractor who told you she was going to build your cabinets out of "wood"; you wouldn't hire a florist who told you he would make your anniversary bouquet out of "plants".
  2. How long will you be on it?
  3. What is the intended benefit of taking this medication?
  4. What are the potential or likely adverse effects for the timeframe in which you'll be on it?
  5. (if applicable) What are the potential interactions with any other prescription medications, over-the-counter medications, supplements, herbs, &c you take?

Doctors have a lot of training, and they do learn how to perform risk analysis, but at the end of the day, you are the one who gets to decide whether the potential benefits of any medication are worth the risks involved. You can't know the benefits or the risks unless you know exactly what you're putting in your body. Ask, and don't put up with bullshit non-answers.
maradydd: (Default)
A bit late for Mother's Day, but great nonetheless.

maradydd: (Default)
My friend [ profile] feonixrift, who is allergic to latex, recently had an unexpected reaction to a roll of athletic tape that was sold as "latex-free". Whilst commiserating with her, I remarked that there really ought to be a straightforward way to determine whether latex was present in a product or not. Reading about the composition of latex, I noted that allergic responses to latex typically have to do with an antigenic protein in the stuff, and she observed that synthetic elastics shouldn't contain protein. I immediately considered and discarded the idea of an ELISA or a Western blot, since both of those tests are not the kind of thing you can do with common household items. However, a little more research turned up the biuret test, which confusingly uses no actual biuret, but does work as an indicator of the presence of protein and is even kind of quantitative.

The biuret test involves small amounts of copper (II) sulfate and potassium or sodium hydroxide, all reagents which I happened to have in my cellar lab. (I get them at the hardware store; USAians can probably find NaOH as drain cleaner and CuSO4 as pool algaecide [h/t [ profile] palecur].) As I had never done a biuret test before and did not know what to expect, I decided to find out what to expect by performing a biuret test on something which I knew had protein in an aqueous solution -- in this case, whole milk.

[ profile] chocolatecoffee took pictures. Here is how you do it. )

It also occurs to me that there are lots of aqueous solutions out there for which protein or an excess thereof is a Bad Thing, e.g., urine. While I do not particularly want to induce proteinuria in myself, I am inclined to find out what my baseline urinary protein levels are like (which will involve working out a way to measure light absorption at 540 nm, i.e., building that spectrometer I've been meaning to build).

More news once I've tested actual latex and some latex-bearing and latex-free athletic tapes. But for now, you can test things for the presence of peptides too!
maradydd: (bad post!)
The medical term for a canker sore is an aphthous ulcer. Aphtha means "ulcer". So a canker sore is ... an ulcerous ulcer.

maradydd: (Default)
When you need to glue crayfish to plastic, or anything else to anything else for that matter, This to That is there.
maradydd: (Default)
Viewed from human scale to city-block-scale, city streets look well-aligned, on a grid, planned out in meticulous detail. (And they are; city planners and surveyors get paid good money to ensure this.)

Viewed from slightly higher up, they look like slime molds:

A fascinating chapter from a book about our friends the Dictyostelia

Now, what I'd like to know is, what are the self-assembly rules for Dictyostelia? What kind of space do they like to have between them and their neighbors?

Well, thanks to the magic of green fluorescent protein, here's how they come together:

Also, their cell signaling has been caught and immortalized on film:

Thanks, internet!
maradydd: (Default)
By way of [ profile] halax, a phylogenetic tree of mixed drinks.

I notice a few glaring omissions -- the Boilermaker should really be down there with the 110 in the Shade, for instance -- but overall I'm quite entertained. Also, LOL at the Kir Royale as the basal clade for the "drinks with champagne in them" clade.

Huh. I notice that the author describes the 110 in the Shade as the "platypuses and slime molds of the drink world". As I'm sure my college and Project A-Kon buddies recall, damn do I love getting my platypus drunk on.
maradydd: (Default)
(and a reference to my gmail address, at that.)

Meredith L. Patterson
Modifies genomes
For profit and fun;

What are the goals of her
Hobbies? Creating an
Army of One.


maradydd: (Default)

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