Thursday, November 29, 2012

Olfactory white

Here’s an interesting tidbit of current sensory research that you can drop into a discussion in your A&P course.

You know how mixing different colors (wavelengths) of light produces a non-color mixture we know as white color?  The mixture of wavelengths make it hard to make out any single wavelength.

You know how mixing different sounds (frequencies) produces a bland hiss we usually call white noise?  The mixture of sounds makes it hard to make out any single sound. So many people use it to block out annoying noises.

Well, researchers in Israel have come up with mixtures of different odorants that produce a bland—almost indescribable—odor that makes it virtually impossible to make out any single odor.  They have nicknamed it white smell or olfactory white.

What good is that, you ask?  If white noise can suppress unwanted noise, then maybe we can use white smell to block out unwanted odors.

That would have some benefit, I suppose, when trapped on an elevator with folks returning from their cigarette break.  I could have used it back in the day when I was a zookeeper, I guess.  But I’m thinking the really critical applications will be for handlers of cadaver dogs and others who routinely encounter really sickening smells.

It didn’t take long after arriving for work at the Elephant House to get used to the odor—we all adapt to it after a few minutes.  But after a disaster, when searchers find one decaying corpse, then find fresh air, then find more putrefied remains, any previous adaptation to the odor will have worn off.  White smell could be very valuable indeed.

Go ahead and wear that annoying cologne—we’re ready for you!

Want to know more?
New smell discovered, and it smells like ... well, who knows?Stephanie Pappas  Live Science on updated 11/19/2012 6:19:55 PM ET[Brief article in plain English summarizes the significance of the discovery]
Perceptual convergence of multi-component mixtures in olfaction implies an olfactory white Tali Weiss et al.
Proceedings of the National Academy of Sciences of the United States PNAS Published online before print November 19, 2012, doi: 10.1073/pnas.1208110109

[Original research article]

Tuesday, November 27, 2012

Joseph Murray, transplant pioneer

Yesterday, the scientific community lost a true pioneer . . . Joseph Murray, who pioneered skin grafting and developed the first successful organ transplant.  In 1954, he transplanted a kidney from one adult twin to his identical sibling.  He continued to pioneer transplant techniques that have saved countless lives.

"In the twentieth century, Joseph Murray . . . noticed that skin he grafted onto burned soldiers he treated during World War II would eventually be rejected by the body. After the war, Murray tried to understand the body’s immune reactions to transplanted tissues and his work led to the first successful kidney transplants. His breakthroughs in transplanting kidneys not only earned him a Nobel Prize in 1990, it also paved the way for all the different types of tissue and organ transplantation that we see today."

93-year-old Joseph E. Murray suffered a stroke on Thanksgiving day and died yesterday in Boston.

I think the occasional story of a pioneer in the history of human science adds a lot to the A&P course.  Such stories give a human dimension to the pursuit of science and provide the context needed for students to understand how we know what we know.

Today we have a sad but important occasion to bring up the amazing accomplishments of Joseph E. Murray with our students.

Want to know more?
  • Joseph E. Murray, Transplant Doctor and Nobel Prize Winner, Dies at 93
    • The New York Times Published online: November 27, 2012
    • [Obituary of Murray]
  • Hope, Innovation: Remembering A Transplant Pioneer
    • Renee Montagne
    • National Public Radio (NPR) Morning Edition Broadcast/published online November 27, 2012
    • [Renee Montagne talks with Dr. Atul Gawande about the life and work of Dr. Joseph E. Murray, who performed the first successful organ transplant in 1954. Murray died Monday at age 93.]
    • Text
    • Audio[4 min 15 sec]
  • Interview with Joseph E. Murray
    • Nobel Web ( Accessed 27 November 2012
    • [Interview with Joseph E. Murray by Sten Orrenius at the meeting of Nobel Laureates in Lindau, Germany, June 2000. Joseph Murray talks about what led him into research; developing transplantation medicine (2:38); and whether breakthroughs in clinical research are often ignored by the Nobel Prize Committee (13:10).]
  • Nobel Lecture by Joseph E. Murray
    • Nobel Web ( Accessed 27 November 2012
    • [Joseph E. Murray held his Nobel Lecture on 8 December 1990, at Karolinska Institutet, Stockholm. He was presented by Professor Hans Wigzell of the Karolinska Institutet.]

Related textbook content
  • Anatomy & Physiology 8th ed.  p. 754, 767, 772-773, 996, A&P Connect: The Nobel Legacy
  • The Human Body in Health and Disease 5th ed. p. 94-95, 154 

Monday, November 19, 2012

Brain injury in high-def with fiber tracking

U. PITTSBURGH (US) — New imaging technology will allow doctors to clearly see for the first time neural connections broken by traumatic brain injury.

Called High Definition Fiber Tracking [1], the technology shows injuries much like X-rays show a fractured bone, according to researchers from the University of Pittsburgh [2] in a report published online in the Journal of Neurosurgery [3].

In the report [4], the researchers describe the case of a 32-year-old man who wasn’t wearing a helmet when his all-terrain vehicle crashed. Initially, his CT scans showed bleeding and swelling on the right side of the brain, which controls left-sided body movement.

High definition fiber tracking reveals loss of fibers, or connections, on the injured right side (yellow) and the intact, undamaged left side (green). The patient was injured in an ATV accident and lost function in his left leg, arm, and hand. (Credit: Walt Schneider Laboratory)

High definition fiber-tracking map of a million brain fibers. (Credit: Walt Schneider Laboratory)
Straight from the Source

A week later, while the man was still in a coma, a conventional MRI scan showed brain bruising and swelling in the same area. When he awoke three weeks later, the man couldn’t move his left leg, arm and hand.

“There are about 1.7 million cases of TBI in the country each year, and all too often conventional scans show no injury or show improvement over time even though the patient continues to struggle,” says co-senior author and neurosurgeon David O. Okonkwo, associate professor in the neurological surgery department.

“Until now, we have had no objective way of identifying how the injury damaged the patient’s brain tissue, predicting how the patient would fare, or planning rehabilitation to maximize the recovery.”

HDFT might be able to provide those answers, says co-senior author Walter Schneider, professor of psychology, who led the team that developed the technology.

Data from sophisticated MRI scanners is processed through computer algorithms to reveal the wiring of the brain in vivid detail and to pinpoint breaks in the cables, called fiber tracts. Each tract contains millions of neuronal connections.

“In our experiments, HDFT has been able to identify disruptions in neural pathways with a clarity that no other method can see,” Schneider says. “With it, we can virtually dissect 40 major fiber tracts in the brain to find damaged areas and quantify the proportion of fibers lost relative to the uninjured side of the brain or to the brains of healthy individuals. Now, we can clearly see breaks and identify which parts of the brain have lost connections.”

HDFT scans of the study patient’s brain were performed four and 10 months after he was injured; he also had another scan performed with current state-of the-art diffusion tensor imaging (DTI), an imaging modality that collects data points from 51 directions, while HDFT is based on data from 257 directions. For the latter, the injury site was compared to the healthy side of his brain, as well as to HDFT brain scans from six healthy individuals.

Only the HDFT scan identified a lesion in a motor fiber pathway of the brain that correlated with the patient’s symptoms of left-sided weakness, including mostly intact fibers in the region controlling his left leg and extensive breaks in the region controlling his left hand. The patient eventually recovered movement in his left leg and arm by six months after the accident, but still could not use his wrist and fingers effectively 10 months later.

Memory loss, language problems, personality changes and other brain changes occur with TBI, which the researchers are exploring with HDFT in other research protocols.

University of Pittsburgh neurosurgeons also have used the technology to supplement conventional imaging, noted Robert Friedlander, professor and chair in the neurological surgery department, who was not involved with the study.

“I have used HDFT scans to map my approach to removing certain tumors and vascular abnormalities that lie in areas of the brain that cannot be reached without going through normal tissue,” he says.

“It shows me where significant functional pathways are relative to the lesion, so that I can make better decisions about which fiber tracts must be avoided and what might be an acceptable sacrifice to maintain the patient’s best quality of life after surgery.”

Okonkwo notes that the patient and his family were relieved to learn that there was evidence of brain damage to explain his ongoing difficulties. The team continues to evaluate and validate HDFT’s utility as a brain imaging tool, so it is not yet routinely available.

“We have been wowed by the detailed, meaningful images we can get with this technology,” Okonkwo says. “HDFT has the potential to be a game-changer in the way we handle TBI and other brain disorders.”

The study was funded by the Defense Advanced Research Projects Agency.

More news from the University of Pittsburgh: [5]

Article reprinted by CC license from
Posted By Anita Srikameswaran-Pittsburgh On March 2, 2012 @ 12:58 pm

URL to original article:

URLs in this post:
[1] High Definition Fiber Tracking:
[2] University of Pittsburgh:
[3] Journal of Neurosurgery:
[4] Read the original study:

Want to know more?

Related textbook content
  • The Human Body in Health and Disease 5th ed. p. 246-254 

Monday, November 12, 2012

New life science journal eLife publishes first articles

Most journals that publish the "big news" in life science breakthroughs, such as Nature and Science, carry with them big price tags for accessing the information they contain.  Unless your institution subscribes, that leaves most A&P professors out of the loop on the information we need to update our courses.  More importantly, it leaves us out of the loop of information that helps us keep the excitement of science alive in our courses.

The Public Library of Science (PLoS) began publishing FREE online science journals a few years ago, and now a new MAJOR free online journal dedicated specifically to the life sciences and biomedicine has emerged.  See for more information

First announced in summer 2011, eLife is a researcher-led initiative for the best in science and science communication. Backed by the Howard Hughes Medical Institute, the Max Planck Society, and the Wellcome Trust, the initiative’s first aim is to launch an open-access journal for outstanding advances in life science and biomedicine, which is also a platform for experimentation and showcasing innovation in research communication.

The eLife journal Web site is set for launch by the end of 2012, but the first collection of articles was released October 15 – listed at the eLife Web site with the full content available at the online archive of the U.S. National Library of Medicine, PubMed Central (PMC), and its mirror sites including UKPMC.

According to Randy Schekman, the journal’s Editor-in-chief, “We see no reason to delay the availability of these discoveries. Our editors have identified them as important, inspiring contributions of the high caliber expected for eLife. So, while the launch of our own journal Web site isn’t expected until December, we will best serve our authors, and science, by just getting them out there.”

eLife’s initial collection of content includes these topics that may be of interest to A&P professors:
  • A hormone involved in response to starvation that dramatically increases the lifespan of mice in which it is overexpressed, although further research into side effects is needed (Zhang et al.).  Information about this discovery will increase student interest in endocrine function, eh?

  • A critical signaling molecule involved in the interaction between a species of single-celled organisms and bacteria – an important advance in efforts to understand the evolution of multicellularity (Alegado et al.).  I often discuss the implications of the serial endosymbiosis theory in my teaching of cell biology— I think this new information may play into that whole scenario.

  • How cells cope with the stress of poorly folded proteins, and specifically how fission yeast deploys the same cellular machinery as other organisms but in an unusual and very different way (Kimmig et al.). I've mentioned the importance of understanding protein folding in A&P many times.

Links to the freely available full text for each article, plain-language summaries (the eLife digest), expert commentaries (Insights), and an editorial describing the motivations behind this move, are available at  I think the eLife digest and the Insights are particularly useful for A&P professors and A&P students to use in expanding their understanding of human structure and function.

Want to know more?
For more information about eLife, visit
To sign up for free updates in the areas that interest you at

Content adapted from eLife press release 

Monday, November 5, 2012

New method to avoid mitochondrial disorders

A recent paper in Nature describes a new approach to avoiding inherited mitochondrial disorders.

Although identified as "germline gene therapy," in the title of the paper the method is a lot like cloning. The method calls for transferring a healthy nucleus out of an egg with mutant mitochondria, then transferring that nucleus to a healthy donor egg.

In this technique, scientists are not making a genetic copy of an individual as an cloning — but the technique is very similar. The whole idea of this is an interesting one to bring up in an A&P course when discussing the topic of mitochondrial inheritance. It not only emphasizes and clarifies the central idea of mitochondrial inheritance, it's also a good way to connect students to "what's going on right now" in the world of science. 

Among the links below I have included an article from Science News that does a great job of summarizing the new research and pointing out some of the ethical concerns that the method poses.

The article also contains a sidebar listing some of the mitochondrial diseases that might be avoided using the technique. That sidebar complements the coverage of mitochondrial inheritance found in my textbooks. 

Check out this video that demonstrates how the method is carried out in the lab.  You can use this video in your course!

Want to know more?
  • Cloning-like method targets mitochondrial diseases: providing healthy ‘power plants’ in donor eggs appears feasible in humans
    • Tina Hesman Saey Science News Web edition: October 24, 2012 Print edition: November 17, 2012; Vol.182 #10 (p. 5)
    • A great feature article that summarizes the discovery in plain English.  Might be the best place to point your students if they want more information.
  • Towards germline gene therapy of inherited mitochondrial diseases. 
    • M. Tachibana et al. Nature. Published online 24 Oct 2012 doi:10.1038/nature11647
    • Abstract of original journal article describing the method. Includes images.

Related articles
  • Embryo transfer technique could prevent maternally inherited diseases | Body & Brain | Science News
  • Mitochondrial DNA replacement successful in Rhesus monkeys | Genes & Cells | Science News

Related textbook content
  • The Human Body in Health and Disease 5th ed. p. 45, 672, A-13 
Here's a related image you can use in your course: