Sunday, April 29, 2007

Cracked fingernails and why they don't split

Fingernails strong by design

If you've ever wondered why cracked fingernails don't just painfully split down the middle or simply been grateful that they don't, Dr. Roland Ennos can tell you why.

Fingernails have three fibrous layers. The outer and inner layer have fibers running in all directions that give the fingernail its flexibility. The outermost layer also wraps around the sides to help prevent cracks from forming in the first place. The thick middle layer has fibers that traverse the nail, sending those cracks laterally instead of into the quick.

To test his theory of nail mechanics, Dr. Ennos attached instrumented scissors to a measuring device and found that nails were twice as difficult to cut towards the base as across it...Consequently cracks are deflected around the end of the nail, protecting the nail bed from damage.

Saturday, April 28, 2007

Stoned lung cancer cells stopped in their tracks!

The beauty of this study is that we are showing that a substance of abuse, if used prudently, may offer a new road to therapy against lung cancer.
--Anju Preet, Ph.D.

Medical marijuana may not be just for nausea and pain control anymore. Dr. Preet and colleagues discovered that THC or Δ-9 tetrahydrocannabinol which is the active ingredient in the drug inhibits the growth and spread of an aggressive form of lung cancer.

Cellular cannabinoid receptors in cells can be activated by endocannabinoids--naturally produced marijuana-ish sorts of molecules--as well as by THC. Once occupied by the right sort of molecule, these receptors participate in various biological functions such as pain and anxiety control, and inflammatory processes. One THC derivative called Marinol has been approved for appetite stimulation in cancer and AIDS patients. Another drug called Acomplia blocks the cannabinoid receptors and is awaiting FDA approval for the metabolic syndrome, a pre-diabetic condition associated with notable weight gain around the waistline.

These Harvard investigators found that THC inhibited the progression of lung cancer cell growth both in petri dishes and in mice. While the mechanism of THC's anti-cancer action is unclear, the researchers speculate that THC may interfere with the formation of the cancer's blood supply.

Tuesday, April 24, 2007

I've recently discovered the origin of the term hightailing as in "I'm going to hightail it out of here." Ninja the cat zipped through the kitchen on some mysterious feline mission with her tail straight up, hightailing her way to whatever her grape-sized brain had in mind.
Miserable cold here. Cold outside, cold in my head. This has been the year for upper respiratory infections, and this is my second one. Makes me wonder, as my patients often ask, "Is there something wrong with my immune system?" My inner doctor says no, I'm just exposed to a lot of sick people. This cold, however, comes to me courtesy of my office manager--you know who you are and what you've done to me!

So I'm practicing what I preach--herbs, aspirin, cough syrup with codeine for night-time cough relief, steroid nasal spray to try to keep the head open and the sinuses clear, Sudafed, and Zyrtec as this all arrived on top of springtime allergies. Like all of you, I don't have time to practice the stay at home and rest thing, I'm off to Albertson's to shop for groceries.

Saturday, April 21, 2007

A woman's heart attack

I just received an e-mail from a reader of my newsletter warning others about the unusual presentations of heart attacks in women. This e-mail describes one woman's attack of 'indigestion' that was, in fact, a heart attack hitting her as she curled up in her recliner reading a book.

I clearly recall a woman coming in to my office in the aftermath of a bout of 'stomach flu' several days previous. She described nausea, vomiting, fatigue, I agreed with her diagnosis, we both agreed she was on the mend. She showed up three days later in congestive heart failure from the massive heart attack she'd suffered that seemed to be stomach flu. When she initially came, it was already to late to save any of her heart, but I certainly took this lesson to heart.

A heart attack may not send you sweating to the racquetball court floor with crushing chest pain. Take unusual and persistent symptoms in your chest or upper abdomen seriously, and call for help sooner than later. No shame in finding out you're really okay instead of finding out too late that you should've sought help.

Friday, April 20, 2007

Light pollution in the US

Blindness and breast cancer

If you want 662 pages worth of reasons to take melatonin at night, do a search on the supplement at There's 15 pages alone on the association between melatonin and breast cancer.

Melatonin is a hormone produced by the pineal gland at the base of our brain when the lights are out. The more we stay up late working at our computers under bright lights, the less melatonin we produce.

I've written before about what a marvelous anti-oxidant melatonin is. Turns out, it has oncostatic (cancer-stopping) properties as well, particularly with respect to estrogen-receptor positive breast cancer. One reason for this protective quality of melatonin may be that it has anti-estrogenic properties that block the stimulation of estrogen to breast tissue.

An extensive review of hospital discharge records years ago by the Centers for Disease Control found that profoundly blind women (all dark all the time) have half the risk of breast cancer compared with their sighted counterparts. Other studies have found a positive association between the degree of visual impairment and the risk of breast cancer.

My neighbors have the spotlight from hell guarding their driveway; a beacon worthy of a lighthouse that brights my bedroom into the lighted equivalent of perpetual dawn. My husband toys with shooting it out, but I'll just keep downing my melatonin. Breast cancer protection AND great dreams!

Thursday, April 19, 2007

New uses for old standbys?

Here's a question recently sent to me via anonymous e-mail:

Does putting listerine in your vagina kill sperm and prevent pregnancy?

NO! Unless, of course, it makes you too sore to use your vagina.

Speaking of novel cures, one of my patients used Lysol to stop vaginal odor. It didn't work and was highly irritating. Not recommended. Another used first a.m. urine to clear her acne. It worked! Try it or not, it's your call.

Tuesday, April 17, 2007

MRI now recommended for high-risk breast cancer screening

Breast cancer screening just got better for women at a high (20-25%) lifetime risk of developing a malignant breast tumor. The American Cancer Society released new screening guidelines this year recommending MRI scans for women with strong family histories of breast cancer.

In 2004, a study of over 1900 high-risk women in the Netherlands compared MRI technology with standard mammograms. Analysis of 45 cancers found over the course of 3 years showed that mammograms detected 18 tumors--10 of which were visible by MRI--and missed 27 tumors. Of 32 tumors found on MRI, 22 were not visible on mammogram. Four tumors arose during the intervals between screening tests, and one tumor was detected only by clinical breast examination.

Because some tumors (nearly 18% in this series) are only detectable by mammograms, the ACS guidelines recommend both MRI and mammographic screening in high risk women. While MRIs are known to be sensitive tests for identifying cancers in very dense breast tissue (which are very hard to read on mammograms), the ACS stopped short of recommending this technique for routine use in women with dense breasts, even though such a breast pattern is associated with a six-fold increased risk of cancer.

Eventually, insurance coverage will follow these guidelines. Meanwhile, I'm considering springing for the $1,000+ test for myself.

Saturday, April 14, 2007

I've been on TV twice in my adult life (we're not counting the Brownie troop's trip to the Sheriff Scotty show here). Both times, I did not wear make-up--boy was that a mistake!--but I did pre-medicate with beta-blockers. As a result, I appeared pathetically pale and totally calm.

Beta- blockers tone down the effects of the sympathetic nervous system. This is the 'fight or flight' arm of the involuntary nervous system which is driven by norepinephrine or adrenalin. Originally developed for hypertension, these drugs were subsequently found to be very useful for stage fright. Several patients of mine who are attorneys take them before they appear in court, and some sales reps use them to calm the pre-presentation jitters.

Evidence suggests that they may someday be used to prevent metatstases from cancer. In particular, studies suggest that many breast, colon, and prostate cancer cells have beta-adrenoreceptors on their surfaces. Men on beta-blockers were 18% less likely to contract prostate cancer in one Canadian study, and propranolol prevented metastases in a mice tumor model.

One cancer biologist noted:

These data imply that emotional stress may contribute to the development of cancer and may also reduce the effectiveness of cancer treatments.

Wednesday, April 11, 2007

Night moves

Those twitchy legs may have more serious consequences than the loss of a decent night's sleep. Canadian researchers at the Hôpital du Sacre-Cœur in Montreal studied the night moves of 10 patients with restless leg syndrome. They found that periodic leg movements during sleep (PLMSs) were associated with significant spikes in blood pressure of 20-40 points.

Restless sleepers may twitch every 20-40 seconds resulting in a whole lot of blood pressure troubles throughout the night. The scientists noted that persons with sleep apnea may suffer from these same spikey nocturnal elevations. Lead author Dr. Paola Lanfranchi concluded:

If someone has heart failure, and every 20 to 40 seconds they have an increase in blood pressure, it's going to have an impact on the function of the heart.

Saturday, April 07, 2007

You appear to have caught that bug that's been going around my
waiting room.
--Doctor to patient in exam room per New Yorker cartoon

Yech, even I wouldn't have wanted to be in my waiting room yesterday!
Advair and lung cancer

I'm sure you've listened to the 'fine print' on televised prescription drug commercials. At the end of the ad, a fast-paced disclaimer rips through the potential death and destruction associated with use of the drug. My nearest and dearest relative with COPD who generally is disinclined to pay attention to any commercials whatsoever chucked his Advair in the trash after hearing out the Advair ad to its end.

Now a bunch of ex-cigarette-smoking old veterans are proving that inhaled steroids (which are part of the Advair formulation) may have additional benefits to outweigh those risks. Over 10,000 of them previously diagnosed with chronic obstructive pulmonary disease were followed for nearly 4 years in order to study the association of inhaled steroid use with the onset of lung cancer. Lung cancer is common in COPD patients and a frequent cause of death in this population.

Those subjects who stuck with their inhalation therapy, sucking in at least 1200 mcg/day of steroids had a whopping 61% decreased incidence of lung cancer over the course of the study. The Seattle investigators postulated that the anti-inflammatory effect of the medication decreased the risk of malignant cell transformations.

Perhaps someday they'll mention that in the TV ads.

Wednesday, April 04, 2007

Don't count on mammograms

The latest issue of the New England Journal of Medicine makes it clear that breast cancer screening via mammograms is a most imperfect science. An editorialist notes that "screening mammography is also the most common basis for lawsuits in radiology, which is not surprising, since 25 to 50% of cases of breast cancer are identified retrospectively on the previous annual screening mammogram."

In other words, when cancer is discovered in a woman's breast, at least 1 in 4 of the tumors can be seen on review of the previous year's mammogram films. Dr. Ferris Hall of Beth Israel Deaconess Medical Center in Boston goes on to note:

Screening mammography, a particularly stressful task for radiologists, is associated with a relatively high rate of burnout. For all these reasons, residents have avoided this field for decades, leaving a shortfall of fellowship-trained mammographers, many of whom are older and overworked.
If you are confused about whether or not to have annual mammograms during your forties, no wonder. Doctors can't agree on this either. Consider the opposing positions:

The reduction in this age group is smaller than that in women 50 years of age or older, is subject to greater uncertainty about the exact reduction in risk, and comes with the risk for potential harms (such as false-positive and false-negative results, exposure to radiation, discomfort, and anxiety).
--Amir Qaseem, M.D., Ph.D., American College of Physicians

This was an incredibly irresponsible decision by the American College of Physicians. They clearly don't understand the screening trials of mammography and they don't understand the data. They just totally misinterpreted things.
--Radiologist Daniel B. Kopans, M.D., of Harvard

The new ACP guidelines suggesting that routine annual mammograms for 40-somethings reopens a debate that was recently 'settled' in favor of yearly exams for through the 40's. Conventional wisdom held that while 40-ish women were less likely to get breast cancer than their older colleagues, their cancers tended to be more aggressive and more frequent screenings were useful to catch faster-growing tumors earlier by looking for them more often.

Women at higher risk for breast cancer due to an inherited predisposition should have earlier screenings PLUS breast MRI scanning. MRI screening, while expensive, is now recommended for all women diagnosed with breast cancer to look for other tumor foci. This recommendation may ultimately extend to women with dense breast tissue on mammogram; breast cancers are harder to visualize in such breasts by mammograms and these women are known to be at a much higher risk for developing malignant tumors, a risk believed to be equivalent to women with BRCA mutations.