How do doctors weigh the risks and benefits of diagnostic tests? Sometimes it's harder than you might think. 

Take CT scans, which deliver known doses of radiation to patients. Add kids, for whom radiation risks are higher -- in part because of their smaller developing bodies and because there's more time ahead to see effects of radiation. Now consider a CT scan for a child with severe and chronic sinusitis. A kid who has come to a specialist after having tried other diagnostics and treatments for their condition. A CT scan has the potential to reveal definitively -- more than any other test -- what's going on. 

I wrote about the risk data and the benefits in practice of using CT scans in kids for ENT Today.

The doses are small, but they do add up. As one ENT doctor told me: “I don’t think much about one CT scan. But I do think about two CT scans.”

Photo credit: thesmokingsection on Flickr

River dams: good for generating electricity but bad for fish. In the Northeast US, many ocean fish species swim into rivers and upstream into small tributaries to spawn -- and complete their life cycle. Dams are a major barrier to these migratory fish and so people have come up with a variety of ways to help get fish around the dams -- from trapping and trucking to structures called fish ladders and elevators. 

For ScienceNOW, I wrote about a new report that looked at the numbers of fish using fish passages on three major river systems: the Merrimack, the Connecticut, and the Susquehanna.  Although stated targets at these dams call for hundreds of thousands of fish to pass through, the actual numbers were in the hundreds, the tens, and in the case of river herring on the Susquehanna, single digits. 

The report's authors make their case for dam removal, saying that other dams -- farther upstream or on less ecologically important waterways -- could make up the power loss. Further they point to Maine, where such radical action has been taken on the Penobscot River. 
photo credit: Wildcat Dunny on flickr

Household mold is certainly an unsightly nuisance, but how bad is it for your health? I looked into the question for the Washington Post. Experts say allergic responses are most common. Toxic mold, on the other hand, is more myth than truth -- at least in terms of inhaling invisible spores and becoming severely ill.

The issue is relevant to those states that suffered Superstorm Sandy's exceptional storm surge, which resulted in many flooded homes. I share some revealing reports from the CDC after Hurricane Katrina and from the Institute of Medicine about the health effects of damp places. 

That's me, examining a dragonfly with a hand lens.  I wrote about these amazing creatures -- and the curious people who chase them -- for Audubon magazine. 

While birding and butterflying have long been popular, watching and identifying dragonflies and damselflies is becoming more so.  Easy-to-use field guides are now available and states such as New York and New Hampshire have done comprehensive surveys to determine what species live there.  In the process of training its residents how to survey, these science/conservation efforts have also bred a loyal group of hobbyists and citizen scientists. 

One dragonfly devotee is Thomas Cullen, who took these photos while introducing me to the ways and wonders of dragonflies and their pursuers.  After I let go of her wings, this female chalk-fronted corporal perched on my hand for several seconds, giving me another, more relaxed perspective.

More data on triclosan, the chemical that makes soap "antibacterial," from the Los Angeles Times health blog.  A research team from UC Davis found untoward effects of the chemical in mice.  Animal evidence is not usually enough to change regulations on a chemical.  But in this case, writer Eryn Brown reminds us, adding the chemical to soap doesn't improve soap's effectiveness.  Hand washing with regular soap and water is a perfectly good germ-killing method. 

Quick post on some of my recent Los Angeles Times articles:

In November 2011, the FDA withdrew its approval for using the drug Avastin in patients with metastatic breast cancer.  Now, two new studies suggest the drug might be helpful in early stage breast cancer.  I parse that confusing message here.

The FDA reneges on one action to reduce antibiotic use in food animals, then moves forward on another. But the agency asserts that both decisions were made in the interest of preserving antibiotics that are medically important for humans. Here's the story.

Health and Human Services secretary Kathleen Sebelius overruled a decision by FDA commissioner Margaret Hamburg to make the so-called morning after pill available without a prescription.  Both parties cite science as basis for their opposing decisions on Plan B. I dig into that science here.

Common sense improvements proposed for school lunches devolve into food vs food fights. For instance, should 1/8 cup tomato paste be counted as a 1/2 cup serving because it's concentrated?

When there's just one cancer drug left to try and you're stuck on the waiting list -- my Los Angeles Times story on drug shortages.

Northe Olague has lived with ovarian cancer six-plus years, with the help of surgery and multiple chemotherapeutic regimens. Earlier this year, tests indicated that her cancer was growing again. Her doctor recommended Doxil, but by the time she was scheduled for treatment, she learned that the drug was unavailable.

Olague: "I was in disbelief."

Oncologist Michael Link, who leads the largest professional organization of cancer care providers: “It’s unfathomable.”

The drug’s maker, Johnson & Johnson, says the shortage was initially caused by production line problems.  The worldwide supply of the drug is made at a single Ohio plant.  Other chemotherapeutic drugs are also in short supply for various reasons, including supply chain economics and doctors' incentives to prescribe pricey brand-name drugs.

My Los Angeles Times article on antibiotic use in agriculture received some outside attention. 

Chris Lindsay of the Critical Wit podcast interviewed me about this and other recent work here. 

And I commented on the issue for This Week in Earth here. 

Antibiotic use in agriculture can lead to antibiotic-resistant bacteria and those bacteria can infect humans.  A new study gave me chance to dig into the issue for the Los Angeles Times.

The study found that the meat you buy at the grocery store is as likely as not to be contaminated with Staphylococcus aureus bacteria, according to researchers who sampled 26 grocery stores in five US cities.  Yep, that’s a 50-50 chance.  Worse, the staph is likely to be resistant to at least one antibiotic drug. 

Farmers who raise food animals can buy feed with antibiotics in them -- the same drugs (or close enough) that are used as medicines in people.  It’s perfectly legal and easy -- no veterinarian to sign off, just money to buy the food.  A whole host of big name organizations -- the World Health Organization, the Centers for Disease Control and Prevention and the American Medical Association to name a few -- condemn this practice and yet it continues.

Photo credit: jon smith photography via Flickr Creative Commons

In my past life, I was a scientist who studied how contextual cues influenced drug action. I published papers in many scientific journals, although never this one: Physiology & Behavior.

In my present life, I’m a journalist who was invited to write for the same journal about anabolic steroids. Steroids are not usually considered drugs of abuse and society’s regulations on their use are quite different than illegal drugs. In a piece the editors were compelled to label “opinion” -- mostly because it did not contain primary data -- I reported on a real-life case study on how the internet aids the misuse of anabolic steroids.

Are artificial food dyes harmless fun? Or do they make kids bounce off the walls? I explored the science behind these contradictory claims for the Los Angeles Times after an FDA advisory panel decided against warning labels for artificially colored foods. Many studies find behavioral effects of food dyes in kids, but they are too small and too variable to act upon.

One thing is for sure -- no harm in avoiding them. As nutrition researcher Laura Stevens says, “One thing about the food dyes, I don’t know of any nutritious foods that they’re in.”

Photo credit: Mouzzy via Flickr Creative Commons

Biologic understanding of the hair follicle, the mini-organ that produces the shafts of keratin we call hair, has advanced by leaps and bounds in the last ten years. Now a handful of biotechnology companies are trying to translate this new knowledge into viable treatments for male pattern baldness and other types of hair loss.

I wrote about the new approaches for Nature Biotechnology (access limited to subscribers), which use cell-based therapies and topical drug cocktails designed to stimulate epidermal stem cells to create new follicles. Hair loss afflicts men, women, and children as a result of aging, disease, and medical treatments. The men's market is so huge, one researcher told me, “It’s mind-boggling.”

Screening for cancer makes so much sense. Find the cancer early -- before symptoms show and tumors have grown and cancer has spread -- and have better chance of survival. However, in practice this is not always so. I wrote about an 18-year study in nearly 80,000 women found no benefit of screening for ovarian cancer for the Los Angeles Times. The lack of benefit couldn't have been more clear: no reductions in deaths, no finding cancers at earlier stages.

For the Los Angeles Times, I wrote about a provocative study out of the Netherlands says that more than 60% of kids diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) might be helped by changes in their diet. The study was significant because it did not exclude kids with known allergies or allergy-related conditions, such as eczema and asthma. And yet, doctors in the US are not exactly jumping on the bandwagon and suggesting dietary overhauls for their patients. (Neither are they doing so in Holland, say the study's author Lidy Pelsser.) The docs I talked to all agreed that there may be dietary triggers in some kids and if parents asked, they would help them plan a dietary intervention. But none were going to suggest trying diet before drugs unless asked.

Last summer I worked on writing an e-book entitle Essentials of Cell Biology for Nature Education, in collaboration with Clare O'Connor, a biology professor at Boston College.

I think cell biology is an acquired taste, personally. I was never particularly interested in it when I was a graduate student or a researcher. But later, when I started my writing career, I often covered cell biology topics and research trends for The Scientist. I was intrigued -- I mean, cells have to take out their own garbage! Soon I was reading Lewis Thomas and I knew I was smitten.

I learned lots of fun facts while working on the e-book. For those of you who know this workflow: DNA to RNA to protein, did you know that it happens thousands of times each second in every cell? Cell biology blows me away.

For February -- American Heart Month -- I reviewed the latest American Heart Association (AHA) guidelines for heart health for the Los Angeles Times. The AHA has boiled their advice down to seven things: some are straight numbers (blood pressure, cholesterol, and glucose) and some are behaviors (not smoking, diet, and exercise) and one is a little bit of both (maintain a healthy weight).

Easy to understand, seemingly easy to do, and yet surveys say that only 1% of Americans actually hit all seven criteria.

Last year I wrote about two brothers who are developing a better epi-pen -- one that's smaller and easier to carry, has a retractable needle, and has clearer label instructions. Eric and Evan Edwards both have life-threatening allergies and they started work on their device when they were still in college. Now they have a patent on their invention in partnership with Virginia Commonwealth University, where Eric is on leave from the medical school. The story can be found here in the Spring 2010 Dean's Discovery Report.

A new study says less is more in breast cancer treatment. I wrote about this counterintuitive finding for the Los Angeles Times. In women with small tumors and signs of lymph node invasion, it turns out that surgically removing cancer-containing lymph nodes from under the arm makes no difference in a woman's survival. Breast cancer experts say this shift in strategy has been a long time coming.

Why wouldn't cutting out cancer help? It's because by the time cancer shows up in lymph nodes, it's proof of escape from the initial tumor site, and many routes are open to spreading cancer cells including the blood and the lymph. "You can't cure metastatic disease with a scalpel," says UCLA's John Glaspy.

In March, I wrote about prostate cancer for the Los Angeles Times, after radio talk show host Don Imus announced he had the disease. Two large studies found that screening for the cancer has had a negligible effect on how many men die from the disease. Rather, more men are getting tests and treatments that may expose them to more harm than the disease itself. One big problem is doctors' inability to determine which prostate cancers will morph into killers and which will remain harmless. One doctor I talked to put it this way, "Prostate cancer is like the cat family. You have house cats and you have tigers."

I wrote several stories for the spring 2009 issue of the Dean's Discovery Report, a biannual newsletter that features faculty researchers and new facilities and centers at the medical school campus of Virginia Commonwealth University.

In the April issue of Nature Biotechnology (subscription only), I reported on a new medicine approved for the treatment of gout -- Uloric (febuxostat) -- the first in 40 years. Three more new drugs are moving through clinical trials and drug-makers are hopeful about their approval by the FDA. The new drugs offer more choices to the limited options doctors have had for decades. And gout, yet another disease of our overconsumptive sedentary lifestyle, is on the rise.

(Image by 19th century caricaturist James Gillray.)