The Third Component of Genetic Blueprint – Writing in Pen (DNA) vs. Pencil (Epigenetics)

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The term epigenetics refers to changes in phenotype (appearance) or gene expression caused by mechanisms other than changes in the underlying DNA sequence, hence the name epi- (Greek: over; above) -genetics. There is no change in the underlying DNA sequence of the organism; the phenotype is expressed by activating some genes while inhibiting others. Epigenetics includes changes in gene function that occur without a change in the sequence of DNA. These changes occur as a result of the interaction of the environment with the genome. Epigenetic determinants activate or silence fetal genes through alterations in DNA, histone methylation and acetylation.


DNA associates with histone proteins to form chromatin. Image source: Wikipedia, GNU Free Documentation License.

From the National Geographic magazine:

"Mother Nature writes some things in pencil and some things in pen. Things written in pen you can't change. That's DNA. But things written in pencil you can. That's epigenetics. Now that we're actually able to look at the DNA and see where the pencil writings are, it's sort of a whole new world."

If you think of our DNA as a piano keyboard and our genes as keys - each key symbolizing a segment of DNA responsible for a particular note, or trait, and all the keys combining to make us who we are - then epigenetic processes determine when and how each key can be struck, changing the tune being played.

Recent studis focuses on a particular epigenetic process called DNA methylation, which is known to make the expression of genes weaker or stronger.

The good news is that some of these processes, unlike our DNA sequences, can be altered. Genes muted by methylation, for example, sometimes can be switched back on again relatively easily. And though it may not happen soon, the hope is that someday epigenetic mistakes will be as simple to repair as a piano that's out of tune.?"


Human chromosomes (grey) capped by telomeres (white). Image source: Wikipedia, public domain.

References:

Twins. National Geographic magazine, 01/2012.

Portrait of twins: series one and series two from National Geographic.

Twins Data Reshaping Nature Versus Nurture Debate. NPR.

Epigenetics, Wikipedia.

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iPad app tests athletes for concussion – Cleveland Clinic video

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An iPad app tests athletes for concussions (a Cleveland Clinic video). The players perform a series of balance, memory, vision, and reaction time experiments to obtain a baseline reading. If they receive a blow to the head during a game or practice, these tests can be redone to determine when it is safe for the athlete to return to action.

References:

Concussion Center - Cleveland Clinic.
Cleveland Clinic Treats Concussions With iPad App. Fox News.

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Risk of heart attack and stroke goes up during holidays – Mayo Clinic video

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From the Mayo Clinic YouTube channel: Are you at an increased risk of heart attack and stroke? Studies show the incidents rise during December and January, but particularly on Christmas Day and New Year's Day. Stay safe.

Jon Lord (70), a Hammond organ player, and a founding member of Deep Purple, who is currently recovering from cancer, says it very well: "Party hearty but look after yourselves. I wish you success and happiness, and above all I wish you health."

Jon Lord - Child In Time, 4 March, 2009, Palace of Arts (MÜPA), Budapest, Hungary.

Happy New Year!

References:

Jon wishes you a Happy New Year

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How to manage your online reputation as a physician in 5 steps

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1. Google yourself - repeat on a regular basis, at least once a month, and set up Google alerts to catch new mentions.

2. Correct mistakes and false information about you that is published online. Contact the site authors.

3. Create your own content - start a blog, Twitter account and Facebook page, use Google+ for draft posts. Send selected news to Twitter, try Facebook for updates from you practice. Link you own blog posts from Twitrter and Facebook.

Setup professional profiles on Google+ and LinkedIn.

Push irrelevant or non-reliable content down in the search results. The farther down the better, as 90% of people won't go past the first page of search results and 99% won't go past page 2.

4. Embrace constructive online criticism. Consider it a 360-degree evaluation.

5. Address actionable items such as "hot button issues" among patients - long waits, lack of response or slow responses.

Cycle of Online Information and Physician Education (click here to enlarge the image). An editable copy for your presentation is available at Google Docs.

I developed the concept of Two Interlocking Cycles:

- Cycle of Patient Education
- Cycle of Online Information and Physician Education

The two cycles work together as two interlocking cogwheels (TIC):

References:

5 ways to manage your online reputation. American Medical News, 2011.

Social media in medicine: How to be a Twitter superstar and help your patients and your practice

Image source: Wikipedia, public domain.

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Kaplan USMLE Step 2 HD Video Neurology Dr Conrad Fisher 2010 Edition – Video

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Here's a sample of the latest KAPLAN USMLE Step 2 Lecture Videos, 2010 edition. Step 2 Course Include the following Subjects: Cardiology, Emergency medicine, Endocrinology, Epidemiology, Gastroenterology, Hematology, Nephrology, Neurology, Obstetrics, Gynecology, Pediatrics, Pulmonology, Rheumatology, Infectious diseases, Psychiatry, Surgery, Dermatology

Link:
Kaplan USMLE Step 2 HD Video Neurology Dr Conrad Fisher 2010 Edition - Video

George Michael, still breathless after pneumonia and tracheotomy, plans a show for his doctors (video)

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Video: George Michael: This has been the worst month of my life. ShowBiz411.

A thin and visibly weak George Michael (48) told reporters outside his home in London that he wasn't supposed to speak for very long and was still recovering from a tracheotomy: "I got streptococca-something... It's a form of pneumonia and they spent three weeks keeping me alive basically," Michael said of the doctors in the Austrian hospital where the singer has been receiving treatment since he fell ill in November.

He added that he also wanted to hold a special show for the Austrian doctors who treated him. "I've spent the last 10 days since I woke up literally thanking people for saving my life."

References:

Gaunt George Michael says "fortunate to be here". Reuters, 2011.

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Mick Jagger (68) on staying fit: "Don’t look at the clouds of tomorrow through the sunshine of today"

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Mick Jagger on staying fit: "You watch what you eat, you exercise, you have a bit of fun. You keep on going forward. Don’t stop. Do what makes you happy. Don’t look at the clouds of tomorrow through the sunshine of today. That’s it."

In other news, you can do anything with a blog (full website and all) - the launch site of Mick Jagger's supergroup SuperHeavy is basically a blog: http://www.superheavy.com

Their new hit "Miracle Worker" plays with medical terminology:

"You have a medical condition.

In an emergency I'm very well prepared
My scalpel, mask and gloves; don't ever get too scared.

No need for anesthetics, I'll go check your charts

You're a Miracle Worker.
You're a surgeon of love."

-- Lyrics from SuperHeavy - Miracle Worker.

Mick Jagger is well-known as an exercise fanatic: "We were busy recording a song and Mick Jagger (68) was doing 120 situps and pushups and singing at the same time time", says Eurythmics founder Dave Stewart.

References:

Mick Jagger's new supergroup with Joss Stone and Dave Stewart. DailyMail.

Redefining age 65 - when your job description is "rockstar"

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40% of police officers have a sleep disorder according to a JAMA study

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More than a third of police officers have a sleep disorder, and those who do are more likely to experience heart disease, problems with job performance and rage toward suspects and citizens, says the NYTimes, citing a study in the JAMA. That figure is at least double the estimated 15-20% rate of sleep disorders seen in the general population.

Having a sleep disorder raised the odds of heart disease by 45%, and the odds of depression by 120%. It also raised the odds of being injured on the job by 22% and falling asleep while driving by 51%.

The JAMA report video.

The officers who had sleep disorders reported more instances of “uncontrolled anger” toward suspects and citizens and serious administrative errors. Sleep deprivation may affect the amygdala, a part of the brain where emotion is governed.

Of the 5,000 study participants, 40% screened positive for at least 1 sleep disorder, most of whom had not been diagnosed previously:

- 34% screened positive for obstructive sleep apnea
- 6.5% for moderate to severe insomnia
- 5.4% for shift work disorder

Not surprisingly, the police officer who had smaller body mass indexes were far less likely to have sleep apnea. System-wide practices can have a significant impact. For example, state police officers in Massachusetts are given one hour of paid exercise time four days a week to help them stay fit. They were less liekly to have sleep apnea.

References:

Sleep Problems in Police Officers Take Heavy Toll. NYTimes.
Sleep Disorders, Health, and Safety in Police Officers. JAMA.

Comments from Twitter:

WendySueSwanson MD (@SeattleMamaDoc): Geesh.

@CrumbedOxygen: wonder if EMS similar.

Dr John Weiner @AllergyNet:  Can CPAP Cure Cops?

Martin Wilson @ChInspMWilson: what is CPAP then ...??

@DrVes CPAP (continuous positive airway pressure) is a treatment option for sleep apnea. Here is more info from the Mayo Clinic: http://www.mayoclinic.com/health/cpap/MM00716

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How to Stay Active With Osteoarthritis: "Motion is Lotion"

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Dr. Daniel Montero, a sports-medicine physician within the Department of Orthopedics at Mayo Clinic in Florida discusses what kind of exercises are you should take part in if you suffer from joint pain. Remember, "motion is lotion", says Dr. Montero.

Exercises you may need to avoid if you have moderate or severe osteoarthritis of the knee or hip include:

- Running and jogging. The difference between how much force goes through your joints jogging or running, as opposed to with walking, is sometimes more than 10-fold your whole body weight

- Jumping rope

- High-impact aerobics

- Any activity where, at any time, you have both feet off the ground at once, however briefly (basketball, jumping)

Fortunately, that leaves a lot of activities that are OK for people with knee and hip osteoarthritis and that can help keep you mobile - see the list at WebMD.

References:

Knee and Hip Exercises for Osteoarthritis. WebMD.

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The "Five Second Rule" doesn’t work

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In case you had any doubts, the "Five Second Rule" doesn't work, says Dr. Susan Rhem, an infectious disease specialist from the Cleveland Clinic:

A common superstition, the five-second rule states that food dropped on the ground will not be contaminated with bacteria if it is picked up within five seconds of being dropped (Wikipedia).

Comments from Twitter:

@alisha764: The "5 Second Rule" doesn't work: Food + Floor = Bacteria

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Stress fractures

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From a 2011 review in the journal American Family Physician:

Stress fractures are common injuries in athletes and military recruits. These typically affect lower extremities.

Symptoms of stress fractures

Stress fractures should be considered in patients who present with tenderness and/or edema after a recent increase in activity or repeated activity with limited rest.

The Barefoot Professor says barefoot running could minimize injuries although this approach is still experimental:

The differential diagnosis of stress fractures includes:

- tendinopathy
- compartment syndrome
- nerve or artery entrapment syndrome
- medial tibial stress syndrome (shin splints) can be distinguished from tibial stress fractures by diffuse tenderness along the length of the posteromedial tibial shaft and a lack of edema

Diagnosis of stress fractures

When stress fracture is suspected, plain radiography should be obtained initially and, if negative, may be repeated after 2-3 weeks for greater accuracy.

If an urgent diagnosis is needed, triple-phase bone scintigraphy (bone scan) or magnetic resonance imaging (MRI) should be considered. Both modalities have a similar sensitivity, but MRI has greater specificity.

Treatment of stress fractures

Treatment of stress fractures consists of:

- activity modification - nonweight-bearing crutches if needed for pain relief
- analgesics
- pneumatic bracing

After the pain is resolved, patients may gradually increase their level of activity.

Surgical consultation may be appropriate for patients with:

- stress fractures in high-risk locations
- nonunion
- recurrent stress fractures

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Controversies in COPD treatment

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Chronic obstructive pulmonary disease (COPD) is a chronic disorder with high mortality rates (one of the top 5 causes of death).

COPD is expected to rise to the third leading cause of death worldwide by 2030. More than 25% of COPD patients have never been smokers.

Some important controversies in COPD management still exist:

- The classic way to define COPD has been based on spirometric criteria, but more relevant diagnostic methods are needed that can be used to describe COPD severity and comorbidity

- Initiation of interventions earlier in the natural history of the disease to slow disease progression is debatable

- There are controversies about the role of inhaled corticosteroids (ICS) in the management of COPD

- Long-term antibiotics for prevention of exacerbation have had a resurgence in interest

New drugs are urgently needed for management of COPD exacerbation.

COPD is a complex disease and consists of several phenotypes that in future would guide its management.

Asthma Inhalers (click to enlarge the image). Advair and Symbicort are FDA-approved for treatment of COPD in the U.S.

References:

Controversies in treatment of chronic obstructive pulmonary disease. Prof Klaus F Rabe MD a , Jadwiga A Wedzicha MD b. The Lancet, Volume 378, Issue 9795, Pages 1038 - 1047, 10 September 2011.

New insights into the immunology of chronic obstructive pulmonary disease. The Lancet, Volume 378, Issue 9795, Pages 1015 - 1026, 10 September 2011.

COPD—more vigorous research needed. The Lancet, Volume 378, Issue 9795, Page 962, 10 September 2011.

Diagnosis and Management of COPD - Current Guidelines

Image source: Enlarged view of lung tissue showing the difference between healthy lung and COPD, Wikipedia, public domain.

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