Injectable Tan?

When I was at the University of Arizona there were various news stories about a so-called "Barbie" drug that stimulated tanning, libido, and weight loss... great right? Perhaps. There were actually two drugs developed at the University of Arizona called Melanotan I and II which are analogs of the naturally occurring hormone called alpha-MSH, or melanocyte stimulating hormone. These drugs and the hormone stimulate (among other things) increased melanin production by melanocytes in the skin, thus leading to increased pigmentation or tanning. When your skin cells or keratinocytes are bombarded with UV light, they release alpha-MSH or closely related peptides that then trigger natural tanning as a protection to UV exposure and damage (see link).

The possibility of an injectable or drug-induced tan is quickly becoming a reality in Europe, Australia, and now even the United States. Clinuvel Pharmaceuticals is performing late stage clinical trials with afamelanotide (or melanotan I) as a photoprotective drug that induces skin pigmentation... tanning. Afamelanotide is being promoted as a photoprotective product to treat several skin disorders that cause photosensitivity, while the drug's use in cosmetic tanning is being downplayed by the company. However, once a drug is eventually approved by agencies like the FDA then doctors are free to prescribe them for "off-label" use which would seemingly include cosmetic tanning. You can only imagine how popular that would be, right? Some concerns exist that melanotan could possibly cause melanocytes to become cancerous (e.g., melanoma). However, safety concerns like these would obviously need to be addressed before the drug is approved for use in people. Note: the potential use of melanotan I and II for sexual dysfunction seems to have been halted due to safety issues and of course the availability of effective drugs like Viagra and Cialis. Melanotan uses in obesity therapy and weight loss seem to be in very early stages at best. See Palatin Technologies for these uses of melanotan.

Read a recent Wire blog entry about melanotan and Clinuvel here at this link.






~ ~ BIO26 ~ ~

Mitral Valve Repair in the news...

This news story/release caught my attention since it involves repair of the mitral valve (aka, the bicuspid or left atrioventricular valve). The repair is interesting since it does not require open heart surgery which might normally be used to repair or replace a leaky mitral valve. Watch the video below from YouTube and follow this link to the news story video if you are interested:



The device is called MitraClip... pretty catchy. Based on what I have read on the internet, the device accomplishes a similar result without opening the chest or arresting the heart. Some surgeons do a similar mitral repair that requires opening the chest and use of a cardiopulmonary bypass machine during the surgery to do the job of the heart and lungs during the 2-3 hour surgery. In contrast, the MitraClip procedure is done via access from the femoral vein and so the patients heart is still beating and the chest is not opened. The cusps or leaflets of the mitral valve are clipped together at the center to reduce the regurgitation or backflow of blood from the left ventricle into the left atrium during ventricular systole.

You might try to figure out how they can access the left atrium via the femoral vein? The LA and systemic veins don't exactly connect up unless you travel through the pulmonary circulations. Not really possible right? Well, turns out the surgeons or interventional cardiologists use whats called a transseptal route to the left atrium. A guide catheter is threaded into the inferior vena cava from the femoral vein up to the right atrium. Then they gain access to the left atrium by simply puncturing through the interatrial septum. Thus the go from the RA to the LA through the heart wall between the chambers... called the septum. Some studies even seem to mention using the fossa ovalis as a landmark or site for the transseptal puncturing.





~ ~ BIO26 ~ ~

All that high-flown medical jargon...

Perhaps you are getting tired of all the jargon and eponyms and overly fancy names thrown around in anatomy/physiology. The medical field amazes me with all its jargon and high-flown language... but then again all those terms do sound cool and make you sound smart when you say them. Maybe that is why doctors and nurses like words like diarthrosis, diaphoresis, dyspnea, dysphonia... imagine life without all these fancy terms. It might sound a little like this Mitchell & Webb Show comedy sketch called "Emergency Medical Treatment"... move over ER, House, and Grey's...




FYI -
For those of you with an iPhone or iPod touch check out the free application called Medical Eponyms, it has tons of terms named after people such as Broca's area or Nissl bodies or my favorite the Sphincter of Oddi. You can also access the database online at eponyms.net

Another great website for those of you with health interests or taking medications is www.rxlist.com where you can look up the details about most all medications. Most include details related to clinical phramacology such as mechanism of action (if known) as well as pharmacodynamics (what the drug does to the body) and pharmacokinetics (what the body does to the drug). You can enter brand name (e.g., Viagra) or generic names (e.g., sildenafil citrate).








~~~BIO25~~~

VOTE! VOTE! VOTE!

Don't forget to VOTE on Tuesday NOVEMBER 4th!

It's the American in You...

~~~~PSA~~~~

Just a shade shy of true wickedness...

What can I say? Halloween makes me think of two things... candy and evil... haha... I heard a song say "I’m just a shade shy of true wickedness" and that made me think about whether we are just a gene shy of true wickedness... in other words is there an "evil gene" that could make humans murderous or overly aggressive or violent. The short answer is no... but there certainly seems to be a tremendous amount of effort attempting to discover a potential genetic basis for social behaviors like aggression or a predisposition to criminal behavior. It is a little scary to think that a monster could be lurking in the human gene pool. But given the complexity of the human behavior and interactions of genes, it seems unlikely that a mutation in a single gene sequence (say adenine to cytosine) during development is going to turn normal humans into serial killers... although it might be a cool movie. During my somewhat futile search for the evil gene I did come across some interesting stuff:

• In the book Hard-Wired (here), author William Clark points out that in the laboratory, rats and mice have been selectively bred for many generations to create strains that are docile or fearful or aggressive with these traits being passed on to each generation each time they breed.
  
• Creating transgenic knockout mice, scientists showed that disrupting a single gene encoding the vassopressin 1B receptor created mice with "reduced levels of social forms of aggression"(here). Genetically introducing a related receptor (vassopressin 1A receptor) into the brain of promiscuous rodents (mating with many partners) transformed them into monogamous (one mating partner), pair-bonding animals (here). Does this mean will will be getting an actual"chill" pill in the future or a monogamy pill for all the cheaters out there? Interesting...
  
• A few years ago, scientists created so called "daredevil mice" by altering one single gene that is highly expressed in the amygdala of the brain. These transgenic mice were more fearless and displayed risk taking behavior not normally seen in mice.
  
• According to an expert commentary in the Journal of the American Academy of Psychiatry and the Law (here), "any attempt to study violent or deviant behavior under the rubric of evil will be fraught with bias and moralistic judgments. Embracing the term evil as though it were a legitimate scientific concept will contribute to the stigma of mental illness, diminish the credibility of forensic psychiatry, and corrupt forensic treatment efforts." Well okay then... deviant behavior gene.
  
• People that carve scary or "evil"pumpkins are 3.5X more likely to commit crimes such as shoplifting, illegal parking, and littering... just kidding. That isn't true. Just my hypothesis.

Take home message? There seems to be no evil gene... maybe we shouldn't even use the term evil in the scientific realm. But certainly, studies of rodents and other species prove overwhelmingly that genes influence social behaviors... and there is likely a cohort or group of genes that influence and/or predispose humans to deviant or bad behaviors. Who knows, someday they might even have a genetic test that will determine if you have an increased risk to commit murder!?


Happy Halloween! Be good.







~~~~~BIO25~~~~~

Brain Strain...

If you watch lots of sports like me then you are also hearing injury news about players. Unfortunately, most of the reports are often inaccurate and vague in terms of the anatomy and the actual structures that have been injured. One distinction to keep in mind is sprain versus strain.

According to the National Institute of Arthritis and Musculoskeletal and Skin Disease:

Sprain is a stretch and/or tear of a ligament. One or more ligaments can be injured at the same time. The severity of the injury will depend on the extent of injury (whether a tear is partial or complete) and the number of ligaments involved. Common examples would be an ankle sprain involving the stabilizing ligaments of the ankle or injury to the ligaments of the knee or shoulder.

Strain is an injury to either a muscle or a tendon. Depending on the severity of the injury, a strain may be a simple overstretch of the muscle or tendon, or it can result from a partial or complete tear. Common examples would be the injury of hamstring muscles (biceps femoris, semitendinosus, semimembranosus) or muscle od the back. So injury of the calcaneal tendon (Achilles) would be a strain.

Over at Stephania Bell's ESPN blog she points out that an injury to the acromioclavicular (AC) joint, since it is stabilized by ligaments around the joint, can be called a sprain. Although, injury at the AC joint tends to separate the acromion process of the scapula from its articulation with the clavicle... and so we would often just call the injury a "shoulder" separation. She implies that, perhaps, when the team would like to downplay an injury they might say shoulder sprain rather than the more serious sounding shoulder separation. Recall in class to make the distinction between shoulder separation, at the AC joint, and shoulder dislocation which occurs at the glenohumeral joint (humerus with scapula). Stephania discusses a term called shoulder sublaxation which refers to the humerus slipping only partially off the glenoid surface, but not completely dislocating out of the glenoid fossa... so there is an additional shoulder injury to think about... shoulder sublaxation. You are practically an orthopedic surgeon or physical therapist if you are still reading this... ha!

Go read the super cool anatomical NFL injury blog at ESPN (Click Here).

~~~~~BIO25~~~~~

Hooray for cheap anatomy and physiology textbooks!

I wanted to proudly display my "new" but used and very cheaply purchased A&P textbook... courtesy of Half.com by eBay. This was purchased and delivered for under $20... the book is in great shape and hardly looks used at all. The publishing date is 2004, luckily not much has changed in the content of A&P books since 2004 so it would be perfect for any anatomy or physiology class. It did take about a week and a half to arrive but if you are not in a hurry... it even had the CDROM, unopened in the back of the book. This is a great alternative to the $125-$210 new textbooks available online and at the Bookstore.

~~~~BIO25~~~~