Highlights from Dr Elizabeth Blackmore’s talk on telomeres and telomerase

Unfortunately because this is a quick post I don’t have time to locate references for some of the things I learned tonight:

• Telomerase levels, and telomere length, are very strongly correlated with a gamut of human health outcomes, from stress to heart rate to longevity to abstract psychometrics like ‘rumination’.
• Telomerase resembles a kind of reverse transcriptase with a built in fragment of RNA that acts both as a kind of primer for the target telomere and as a functional moiety.
• Longevity has a far greater inherited component that I knew, but this only seems to kick in over the age of 75. Past that age, higher telomerase levels and longer telomeres have a strong negative correlation with geriatric diseases such as cancer and cardiovascular disease.
• Telomerase isn’t just good for extending telomeres. Even if RNA interference is used to disrupt the RNA portion of the enzyme, making it impossible for it to bind to DNA, telomerase levels have strong phenotypic correlates. In one experiment, induced higher telomerase levels lead to stem cell proliferation – the mouse model became a ball of fur because it had such a high density of new follicular cells.

Overall the talk was a perfect balance of hard science and human interest. Dr Blackmore is an excellent speaker and I strongly recommend seeing one of her presentations if you have the chance.

Antibiotics: a rant

From ScienceDaily:

Only five per cent of cases were caused by organisms that would require more expensive and broad-spectrum antibiotics, and these cases were nearly all in patients who’d had frequent hospital admissions or were residents of nursing homes.

“The study results show that current Australian guidelines for prescribing antibiotics for pneumonia are appropriate,” Dr Charles said.

“It shows that Australian doctors should resist the push which is occurring in some parts of the world – particularly the US – to prescribe broad spectrum antibiotics to treat essentially all possible causes.”

Golden Staph: It's coming to get ya

If you don’t think antibiotic resistance matters, you’re not living on the same planet I am. About a week ago, a friend went to the doctor with a racking cough. He was given a cursory examination and proscribed a course of amoxicillin. He took it for a few days, gave up when the cough improved mildly, then went back when it started again and was prescribed clarithromycin. At no point was a microbial workup ordered, although he’s now had the cough so long he could have had four with time to spare. To cap it off, he declared yesterday that he was cured and that he was ready to ‘throw out the pills’. Horrified, I asked if the doctor had warned him to take the full course, for his own sake as well as to minimise the risk of acting as the unwitting human incubator for a deadly resistant strain. Of course not. (If you don’t know about superbugs, check out this Wikipedia article).

I’m not a doctor. I’m sure that thousands of antibiotics are prescribed for thousands of coughs all over the world every day, and I’m sure that doctors have good reasons for what they’re doing. But there is no excuse for not telling a patient not to take the full course of antibiotics, and to make damn sure they remember. There is no practical reason why they can’t at least offer a microbiological workup if the disease is more than a common cough, if only for the patent’s piece of mind. If you’re a patient who regularly insists on antibiotics to treat common colds and coughs which are almost certainly viral, shame on you and your doctor. (Again, if you don’t know already: antibiotics do not kill viruses!) Antibiotics are fantastic things which have had a large part to play in our increasing lifespans and quality of life. If you need one, then by all means take one. Just remember to take the full course. If you don’t think you need one, or think your doctor is writing a prescription just to get you out the door as fast as possible, ask.

Don’t take an anonymous blogger’s word for all this; take it from the experts. Misuse of antibiotics: Just Say No.

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