Wednesday, March 11, 2009

JACS Finally Redeemed Itself

JACS sucks and I have commented on this before. This is how I usually read JACS: I scan through the abstract graphics and look for organic structures. If there are pretty nanotubes or clouds or lightning bolts or puzzle pieces, etc., then I skip it. That is until I stumble on an abstract graphic with a sperm cartoon.


So I read further. And these guys actually made this thing above so that they could release progesterone using light. You hit the compound with a laser and it releases progesterone. And you ask "Why is that useful and what is the deal with the sperm?" They used this technique to measure changes in the swimming pattern of human sperm in the presence of progesterone. That got me curious. Then this sentence at the end of the paper got me really curious.

"Supporting Information Available: Full experimental details, UV, 1H, and 13C NMR spectra, full characterization of all new compounds described herein, full experimental details of the
photochemical studies, sperm preparation, and biological measurements." Emphasis mine.

Yep. Sperm preparation. So I had to go to the supplemental info file. And here is how they "prepare" the sperm:

"Sperm Preparation: Human semen samples were obtained from healthy volunteers. Fresh ejaculates were allowed to liquefy at room temperature for 30–60 min. Sperm were purified by a “swim-up” procedure. About 2 ml liquefied semen was layered at the bottom of a 50 mL falcon tube, which contained ~ 4 mL of human tubal fluid (HTF). HTF comprised (in mM): 97.8 NaCl, 4.69 KCl, 0.2 MgSO4, 0.37 KH2PO4, 2.04 CaCl2, 0.33 sodium pyruvate, 21.4 sodium lactate, 2.78 glucose and 21 HEPES, adjusted to pH 7.3-7.4 with NaOH. Motile sperm were allowed to swim up in HTF at 37 oC for 60–90 min. “Swim-up” sperm were pooled and washed 3 times (900×g, 15 min, RT). Number of sperm was determined in a Neubauer cell counter. Washed sperm were resuspended in HTF containing 4 mM NaHCO3 and 3 mg mL-1 human serum albumin (HSA) (Irvine Scientific, USA) (HTF++) at a density of 2 × 107 mL-1 This sperm suspension was incubated for 2-3 h at 37 oC and then used for further experiments."

You think organic chemistry sucks. Imagine having to purify some "healthy volunteer's" sperm. And since when is a fresh ejaculate not "liquified" at room temp?

7 comments:

james said...

I wish i could purify my compounds by allowing them to swim up a tube.

scientist 1 said...

Don't you typically purify your compounds by letting them swim down a tube?

Mike said...

What I want to know is this: Who are these "healthy volunteers" and how fresh are the samples? Do they get them from a sperm bank? Is there a "movie room" in their lab where the guys can go and "relax"??

"Hey 'sperm guy'! I'm feeling a bit randy today. You in the mood for running some experiments? Just give me 5 minutes...."

scientist 1 said...

I think being called 'Hey sperm guy' would be even worse than purifying and prepping the samples.

I see a business opportunity here. We design a automated sample prep and purification system, and attach it to the back of a sex doll's face. You could even mount it to a wall in a sample collection room, and the purified material would come out the other side for the researchers to use right away. It would be like the double blind glory hole of science.

Mike said...

I know what my new NIH proposal is going to be about now.

Dr. Miller said...

double-blind glory hole. Wow.

Brandon said...

Why couldn't they just use Dr. Miller's stomach contents?