Friday, September 21, 2007

Questions from Class

hiya guys...i just wanted to follow up with some answers to questions you had in class the other day:

Q: is Hodgkin's Lymphoma named after the same Hodgkin from the Hodgkin and Huxley model?
A: It appears: NO. At least according to Wikipedia:

Hodgkin's lymphoma, also known as Hodgkin's disease, is named for Thomas Hodgkin in 1832, who first described it. However, it was Sir Alan Lloyd Hodgkin, the British physiologist and biophysicist, who won the 1963 Nobel Prize in Physiology or Medicine for his work with Andrew Fielding Huxley on the basis of nerve "action potentials."'s_disease

Q: What were Hodgkin and Huxley's intellectual backgrounds?
A: Again, according to wikipedia, both are/were physiologists and biophysicists.

Q: What is the time window for performing TTX experiments?
A: I don't know, but I did find a study in which the investigators applied it for 4 hours and another applying TTX for 48 hours.

Q: What are Hydropathy Units a measure of?
A: I got this from:
Biro, JC. "Amino acid size, charge, hydropathy indices and matrices for protein structure analysis." Theor Biol Med Model. 2006; 3: 15.

Hydropathy (hydrophobicity vs. hydrophilicity or lipophobicity vs. lipophilicity) is usually characterized by numbers (hydrophobic moments, HM) from -7.5 (Arg) to 3.1 (Ile), whereas hydrophobicity is a measure of how strongly the side chains are pushed out of water. The more positive a number, the more the amino acid residue will tend not to be in an aqueous environment. Negative numbers indicate hydrophilic side chains, with more negative numbers indicating greater affinity for water.

1 comment:

Nava said...

Thanks for the answers.

Regarding death from TTX, if the cell is dead does its electrical properties change noticeably?
That is, can we learn as much about channel current from a dead cell as from a live one. The electric potentials are still there, aren't they?