Tuesday, November 29, 2011

Caffeine strengthens synapses

Can caffeine help us learn A&P (or anything else)?  Can it improve our memory?

Recent research published in Nature Neuroscience this week suggests that the answer may be yes.  In animal studies, caffeine strengthened synaptic connections in the hippocampus of the brain.  That's not enough to demonstrate that caffeine will be an effective learning enhancer . . . but is does suggest the possibility.

We've been talking about synapses and memory in our A&P 1 course recently, so I thought you might also.  And perhaps want to drop in this tidbit about the latest research.

Next time our students ask how they can possibly remember everything in the A&P course, perhaps a trip to the campus coffee shop may be in order, eh?

Want to know more?
Coffee delivers jolt deep in the brain
Laura Sanders
Science News Web edition : Monday, November 21st, 2011

[A brief synopsis discussing the discovery.]

Caffeine-induced synaptic potentiation in hippocampal CA2 neurons
Stephen B Simons, et. al.
Nature Neuroscience (2011) Published online 20 November 2011 doi:10.1038/nn.2962

[The original research article]

Monday, November 21, 2011

Touch sense is enhanced by deafness gene

Voltage-gated K+ channel protein KCNQ4
We recently discussed the role of ion channels in membrane potentials of excitable cells in my A&P class.  I don't think my students believe me when I say that ion channels are a "hot area" of neuroscience research and that understanding them better will lead to all kinds of new insights about how our nervous system works.

Well, today in Nature Neuroscience researchers reveal that a gene for a protein in voltage-gated potassium channels in sensory cells that is mutated in a form of progressive deafness is also responsible for helping us sense vibration in the skin.  When the gene is mutated, it limits hearing.  But the mutation heightens touch sensitivity in the skin. 

So folks with this form of deafness lose hearing but gain touch sensitivity. 

However, there doesn't seem to be any measurable advantage to the increased touch sensitivity.  Probably, there is a disadvantage.

The important thing here, I think, is that it shows us something about how this particular potassium ion channel, which inhibits neuron excitability, can be used to adjust the sensitivity of sensory neurons for touch.

Studies such as this help us understand that certain genes can be expressed in different cells and have similar functions--but different roles to play.  It also underscores the tendency of the human body to make more than one use of a particular process. 

If our A&P students start looking for the same mechanisms that appear in different parts of the body, then they'll gain a deeper understanding of human structure and function.

Want to know more?

Deafness Gene Heightens Touch
Tia Ghose
TheScientist November 20, 2011 

[Brief news article summarizing the discovery]

KCNQ4 K+ channels tune mechanoreceptors for normal touch sensation in mouse and man

M. Heidenreich, et. al.
Nature Neuroscience  20 November , 2011

[Original research article]

Monday, October 3, 2011

Dendritic cell pioneers win Nobel Prize

The Nobel Assembly at Karolinska Institutet has today decided that

The Nobel Prize in Physiology or Medicine 2011
shall be divided, with one half jointly to
Bruce A. Beutler and Jules A. Hoffmann
for their discoveries concerning the activation of innate immunity
and the other half to
Ralph M. Steinman
for his discovery of the dendritic cell and its role in adaptive immunity



This year's Nobel Laureates have revolutionized our understanding of the immune system by discovering key principles for its activation.
Scientists have long been searching for the gatekeepers of the immune response by which man and other animals defend themselves against attack by bacteria and other microorganisms. Bruce Beutler and Jules Hoffmann discovered receptor proteins that can recognize such microorganisms and activate innate immunity, the first step in the body's immune response. Ralph Steinman discovered the dendritic cells of the immune system and their unique capacity to activate and regulate adaptive immunity, the later stage of the immune response during which microorganisms are cleared from the body.
The discoveries of the three Nobel Laureates have revealed how the innate and adaptive phases of the immune response are activated and thereby provided novel insights into disease mechanisms. Their work has opened up new avenues for the development of prevention and therapy against infections, cancer, and inflammatory diseases.

Two lines of defense in the immune system

We live in a dangerous world. Pathogenic microorganisms (bacteria, virus, fungi, and parasites) threaten us continuously but we are equipped with powerful defense mechanisms (please see image below). The first line of defense, innate immunity, can destroy invading microorganisms and trigger inflammation that contributes to blocking their assault. If microorganisms break through this defense line, adaptive immunity is called into action. With its T and B cells, it produces antibodies and killer cells that destroy infected cells. After successfully combating the infectious assault, our adaptive immune system maintains an immunologic memory that allows a more rapid and powerful mobilization of defense forces next time the same microorganism attacks. These two defense lines of the immune system provide good protection against infections but they also pose a risk. If the activation threshold is too low, or if endogenous molecules can activate the system, inflammatory disease may follow.
The components of the immune system have been identified step by step during the 20th century. Thanks to a series of discoveries awarded the Nobel Prize, we know, for instance, how antibodies are constructed and how T cells recognize foreign substances. However, until the work of Beutler, Hoffmann and Steinman, the mechanisms triggering the activation of innate immunity and mediating the communication between innate and adaptive immunity remained enigmatic.

Discovering the sensors of innate immunity

Jules Hoffmann made his pioneering discovery in 1996, when he and his co-workers investigated how fruit flies combat infections. They had access to flies with mutations in several different genes including Toll, a gene previously found to be involved in embryonal development by Christiane Nüsslein-Volhard (Nobel Prize 1995). When Hoffmann infected his fruit flies with bacteria or fungi, he discovered that Toll mutants died because they could not mount an effective defense. He was also able to conclude that the product of the Toll gene was involved in sensing pathogenic microorganisms and Toll activation was needed for successful defense against them.
Bruce Beutler was searching for a receptor that could bind the bacterial product, lipopolysaccharide (LPS), which can cause septic shock, a life threatening condition that involves overstimulation of the immune system. In 1998, Beutler and his colleagues discovered that mice resistant to LPS had a mutation in a gene that was quite similar to the Toll gene of the fruit fly. This Toll-like receptor (TLR) turned out to be the elusive LPS receptor. When it binds LPS, signals are activated that cause inflammation and, when LPS doses are excessive, septic shock. These findings showed that mammals and fruit flies use similar molecules to activate innate immunity when encountering pathogenic microorganisms. The sensors of innate immunity had finally been discovered.
The discoveries of Hoffmann and Beutler triggered an explosion of research in innate immunity. Around a dozen different TLRs have now been identified in humans and mice. Each one of them recognizes certain types of molecules common in microorganisms. Individuals with certain mutations in these receptors carry an increased risk of infections while other genetic variants of TLR are associated with an increased risk for chronic inflammatory diseases.

A new cell type that controls adaptive immunity

Ralph Steinman discovered, in 1973, a new cell type that he called the dendritic cell. He speculated that it could be important in the immune system and went on to test whether dendritic cells could activate T cells, a cell type that has a key role in adaptive immunity and develops an immunologic memory against many different substances. In cell culture experiments, he showed that the presence of dendritic cells resulted in vivid responses of T cells to such substances. These findings were initially met with skepticism but subsequent work by Steinman demonstrated that dendritic cells have a unique capacity to activate T cells.
Further studies by Steinman and other scientists went on to address the question of how the adaptive immune system decides whether or not it should be activated when encountering various substances. Signals arising from the innate immune response and sensed by dendritic cells were shown to control T cell activation. This makes it possible for the immune system to react towards pathogenic microorganisms while avoiding an attack on the body's own endogenous molecules.

From fundamental research to medical use

The discoveries that are awarded the 2011 Nobel Prize have provided novel insights into the activation and regulation of our immune system. They have made possible the development of new methods for preventing and treating disease, for instance with improved vaccines against infections and in attempts to stimulate the immune system to attack tumors. These discoveries also help us understand why the immune system can attack our own tissues, thus providing clues for novel treatment of inflammatory diseases.


Bruce A. Beutler was born in 1957 in Chicago, USA. He received his MD from the University of Chicago in 1981 and worked as a scientist at Rockefeller University in New York and the University of Texas in Dallas, where he discovered the LPS receptor. Since 2000 he has been professor of genetics and immunology at The Scripps Research Institute, La Jolla, USA.
Jules A. Hoffmann was born in Echternach, Luxembourg in 1941. He studied at the University of Strasbourg in France, where he obtained his PhD in 1969. After postdoctoral training at the University of Marburg, Germany, he returned to Strasbourg, where he headed a research laboratory from 1974 to 2009. He has also served as director of the Institute for Molecular Cell Biology in Strasbourg and during 2007-2008 as President of the French National Academy of Sciences.
Ralph M. Steinman was born in 1943 in Montreal, Canada, where he studied biology and chemistry at McGill University. After studying medicine at Harvard Medical School in Boston, MA, USA, he received his MD in 1968. He has been affiliated with Rockefeller University in New York since 1970, has been professor of immunology at this institution since 1988, and is also director of its Center for Immunology and Immune Diseases.

Key publications:

Poltorak A, He X, Smirnova I, Liu MY, Van Huffel C, Du X, Birdwell D, Alejos E, Silva M, Galanos C, Freudenberg M, Ricciardi-Castagnoli P, Layton B, Beutler B. Defective LPS signaling in C3H/HeJ and C57BL/10ScCr mice: Mutations in Tlr4 gene. Science 1998;282:2085-2088.
Lemaitre B, Nicolas E, Michaut L, Reichhart JM, Hoffmann JA. The dorsoventral regulatory gene cassette spätzle/Toll/cactus controls the potent antifungal response in drosophila adults. Cell 1996;86:973-983.
Steinman RM, Cohn ZA. Identification of a novel cell type in peripheral lymphoid organs of mice. J Exp Med 1973;137:1142-1162.
Steinman RM, Witmer MD. Lymphoid dendritic cells are potent stimulators of the primary mixed leukocyte reaction in mice. Proc Natl Acad Sci USA 1978;75:5132-5136.
Schuler G, Steinman RM. Murine epidermal Langerhans cells mature into potent immunostimulatory dendritic cells in vitro. J Exp Med 1985;161:526-546.

illustration High resolution image (pdf 3,6 Mb) 

The Nobel Assembly, consisting of 50 professors at Karolinska Institutet, awards the Nobel Prize in Physiology or Medicine. Its Nobel Committee evaluates the nominations. Since 1901 the Nobel Prize has been awarded to scientists who have made the most important discoveries for the benefit of mankind.

Nobel Prize® is the registered trademark of the Nobel Foundation 

The information above is taken directly from 
The 2011 Nobel Prize in Physiology or Medicine - Press Release
Nobelprize.org. 3 Oct 2011 my-ap.us/pE7zzC

Want to know more?
Immune Responses
[An animated activity from the Nobel Prize folks.] 

Find a brief explanation of dendritic cells in these textbooks:
Find FREE images and videos you can use in your course
Dendritic cells

Watch a brief video on dendritic cells.

Sunday, August 7, 2011

Bookmark time again!

As you begin another term of A&P, don't forget to stock up on those FREE eyeball bookmarks for your students!

These bizarre "first day of class" gifts for your students include information for your students on how to access my blog The A&P Student.  This blog has a continuously updated library of study tips for A&P, shortcuts, links to learning resources, and more.

These bookmarks are available in packs of 50 to qualified A&P instructors.  And if you act now, you'll also get some fun freebies for yourself!

Get your free bookmarks here: my-ap.us/99NNTx

Wednesday, June 8, 2011

That weird E. coli epidemic

Remember my previous post, in which I gave you a free slide show on the role of the appendix in keeping the gut microbiome happy?  Well, to sort of "prove the point" of the importance of a healthy gut microbiome, we've been hearing all about that weird Escherichia coli (E. coli) epidemic in Europe.

If you're like me, you'll want to take the opportunity to emphasize concepts learned in class by applying them to "real life" events reported in the news.  If you're like me, you may want to check out these journal articles:

Deadly bugs: Toxin-producing E. coli strain causes outbreak in Germany
Tina Hesman Saey
Science News web edition : Tuesday, June 7th, 2011

[Brief, highly readable introduction to the current outbreak in Europe.  Plus a cool photo!]

Bacterial infections: new and emerging enteric pathogens
Sherman, P et al.
Current Opinion in Gastroenterology:January 2010 - Volume 26 - Issue 1 - p 1-4
doi: 10.1097/MOG.0b013e328333d73b
[from the abstract: "The aim of this review is to highlight recent advances in knowledge of bacterial enteric infections. We focus on understanding of enterohemorrhagic Escherichia coli O157:H7 and Campylobacter jejuni infections, and to link these acute events with long-term consequences in a susceptible host, including irritable bowel syndrome and chronic inflammatory bowel diseases."]

Clinical Relevance of Shiga Toxin Concentrations in the Blood of Patients With Hemolytic Uremic Syndrome
Brigotti, Maurizio et al.
Pediatric Infectious Disease Journal: June 2011 - Volume 30 - Issue 6 - pp 486-490
doi: 10.1097/INF.0b013e3182074d22

[from the abstract: "Intestinal infections with Shiga toxin-producing Escherichia coli (STEC) in children can lead to the hemolytic uremic syndrome (HUS). Shiga toxins (Stx) released in the gut by bacteria enter the blood stream and target the kidney causing endothelial injury. Free toxins have never been detected in the blood of HUS patients, but they have been found on the surface of polymorphonuclear leukocytes (PMN)."]

Infectious colitis
Navaneethan, Udayakumar and Giannella, Ralph A
Current Opinion in Gastroenterology: January 2011 - Volume 27 - Issue 1 - p 66–71
doi: 10.1097/MOG.0b013e3283400755

[from the abstract: "The incidence of gastrointestinal infections continues to increase and infectious colitis contributes to significant morbidity and mortality worldwide. The purpose of this review is to highlight the recent advances in knowledge of pathogens causing infectious colitis. We describe the various pathogens and specifically focus on enterohemorrhagic Escherichia coli (EHEC) O157:H7, Salmonella, Shigella, Campylobacter, and Entamoeba histolytica infections, and their impact on long-term effects, including postinfectious irritable bowel syndrome and inflammatory bowel disease."]

An inside job: subversion of the host secretory pathway by intestinal pathogens
Sharp, Tyler M and Estes, Mary K
Current Opinion in Infectious Diseases: October 2010 - Volume 23 - Issue 5 - p 464–469
doi: 10.1097/QCO.0b013e32833dcebd

[from the abstract: "The cellular secretory pathway, composed of the endoplasmic reticulum, Golgi apparatus, and cellular vesicles, mediates the intracellular trafficking of proteins and lipids. Gastrointestinal pathogens frequently affect the functions of enterocytes, the differentiated cells involved in secretion and absorption of extracellular molecules. Microbial pathogenesis can be enhanced by altering the trafficking of key molecules such as brush border enzymes, soluble immune mediators such as cytokines and chemokines, and MHC Class I molecules, all of which rely on the secretory pathway for their appropriate cellular localization. This review focuses on our current understanding of the distinct mechanisms employed by enteric pathogens to antagonize the secretory pathway."]

Probiotics: progress toward novel therapies for intestinal diseases
Yan et al.
Current Opinion in Gastroenterology: March 2010 - Volume 26 - Issue 2 - p 95–101
doi: 10.1097/MOG.0b013e328335239a

[from the abstract "As the beneficial effects of probiotics on health and disease prevention and treatment have been well recognized, the demand for probiotics in clinical applications and as functional foods has significantly increased in spite of limited understanding of the mechanisms. This review focuses on the most recent advances in probiotic research from genetics to biological consequences regulated by probiotics and probiotic-derived factors."]

For a really cool, copyright-free image to use in your course, go to my-ap.us/lVEg69

Monday, May 9, 2011

FREE animated function of the appendix

When in comes to explaining the role of the human vermiform appendix, I must dispel students' belief that it has no role. And then I must try to convey that it has an immune function while at the same time promoting microbial growth.

Being a visual learner by preference, and therefore preferentially a visual teacher, I find any concept easier to teach if I can draw a picture of it.  Even better if I can put that picture into motion.

I recently uploaded a new set of animated PowerPoint slides that anyone can use to explain the immune function of the appendix.

To download and view the FREE set of slides, go to http://www.mediafire.com/file/jqgizrv1xr8s6kd/AppendixFunction-LionDen-KPatton.pptx

To access the file, you'll need a password.  If you don't already have a current password to the Lion Den Slide Collection, you can get one by filling out the form at http://my-ap.us/eOtyVq

Feel free to use it in your classroom or website (or both).

I'll be adding a narrated version to my YouTube channel soon at youtube.com/user/kevintpatton

Want to know more?
New "old" news about the appendix
K. Patton
The A&P Professor 24 Aug 2009
[From the archive of this blog, includes some interesting comments from our readers plus links to journal articles]

The Cecal Appendix: One More Immune Component With a Function Disturbed By Post-Industrial Culture
Michel Laurin et al.
The Anatomical Record. Article first published online: 2 MAR 2011 DOI: 10.1002/ar.21357
[Recent review article that outlines an interesting perspective on the function of the appendix.]

Monday, May 2, 2011

Video: Neutrophils to the Rescue

Have you seen this video from Science Videolab that shows fluorescent-stained neutrophils rushing toward the site of a tissue injury?

The clip actually strings together several videos showing bright green neutrophils rushing toward damaged cells in liver tissue (seen as bright red areas).  The narrator explains in simple terms what is going on and what it means in understanding what happens when tissue damage occurs.

This is a great FREE video to show your class when discussing any or all of these topics:
  • WBCs in general
  • Neutrophils
  • Immune response
  • Inflammation
  • Chemotaxis
Check out the video!
Want to know more?
Intravascular Danger Signals Guide Neutrophils to Sites of Sterile Inflammation
Braedon McDonald et al.

15 October 2010: Vol. 330 no. 6002 pp. 362-366 DOI: 10.1126/science.1195491

[Research article that summarizes the discovery about how neutrophils use a multistep process to navigate toward noninfectious sites of tissue injury. ]

EDITORS' CHOICE: Immunology Inflammation Response in Living Color
Kristen L. Mueller
Sci. Signal., 19 October 2010 Vol. 3, Issue 144, p. ec324 DOI: 10.1126/scisignal.3144ec324
[Editor's summary of the processes described above]

Monday, April 25, 2011

Supplementary courses help A&P students succeed

A few years ago, we brainstormed about what else we could do as A&P professors to help our students succeed.  We realized that the two most common things holding our students back from reaching their full potential were:
  1. Lack of adequate preparation to begin A&P on a solid footing
  2. Lack of basic learning and study skills 
With the typical A&P course involving an unrelenting flood of facts, concepts, and applications, a lack of preparation and study skills can be catastrophic.

To address the lack of preparation, we have a prerequisite of "C or better in high school biology or its equivalent within the last five years."  That's the best we could manage given the constraints of our institution and its programs.  But even with the most stringent prerequisites, it's rare that students really walk into an A&P class ready with a comfortable foundation in biological chemistry and cell biology.

So I developed a refresher course that incoming A&P students could take just before entering their A&P 1 course.  Foundations in Science for Health Careers is a developmental level, one-hour course that is offered in a completely online self-paced format.  We offer it only during the short mini-mesters and half-semesters.

The Foundations course covers the basic chemistry and biology concepts students need as they begin A&P.

To address the lack of study skills, I developed a one-credit course for our A&P 1 students to take along with A&P 1.  Having been given the idea of a supplemental course by my friend Mari Hopper at Southern Indiana University, we began offering A&P 1 Supplement at our institution.

This course parallels the A&P 1 course, giving students how-to tips on specific study skills useful in A&P.  Students also have the opportunity to bring their sticking points to the class to get help in getting them unstuck.

The Foundations course is the refresher course and the Supplement course is the shortcut course.

Want to know more? 

Check out my video . . .

Viewing this content requires Silverlight. You can download Silverlight from http://www.silverlight.net/getstarted/silverlight3.

Then check out the handout and helpful links at The A&P Professor website:

SEMINAR: Helping Students Succeed

Do these courses work?  We're still working on the statistics, but as the above presentations tell you, student feedback from anonymous surveys show that students are happy with what they are getting from these courses.  When we get some statistical analysis done, I'll let you know!
[NOTE: If your students would like to take our online pre-A&P refresher course (BIO 095 Foundations in Science for Health Careers) prior to taking your A&P course, they can enroll at St. Charles Community College during either of two 5-wk summer sessions or during either of two 1-wk pre-fall sessions . . . or beyond.]

Monday, April 18, 2011

First human brain map unveiled

Today NewScientist reported that the world's first computerized map of the brain was unveiled last week by neuroscientists at the Allen Institute for Brain Science.

The FREE interactive brain map must be downloaded and installed on your computer at http://my-ap.us/f8Rabf   It's fun . . . you should try it! 

You can see both of two brains used to produce the maps and check which parts of the brain you want to see.  Each is shown in a different color and you check and uncheck brain parts as you explore.  For example, you can visualize just the cerebral nuclei, then add in the cerebral cortex.  You can also click on each part of the cortex and it will highlight (and name) the particular gyrus or region that you are on.

There are far more features than I've had the time to explore . . . and far more than I'll need to use in the classroom to help my students visualize the brain's structure.

All these richer features are available because it's meant as a research tool rather than a teaching tool.  The new map can show the biochemistry and gene expression at various sites based on in depth studies done on two human brains, for example.  But you don't have to use any of the richer features.

One of many interesting and useful tidbits of information that has come out of the research end of the project is that there is a 94% similarity in the biochemistry of the two human brains used int he study.

Another interesting fact is that at least 82% of all human genes are expressed in the human brain.  (Except perhaps in mine, especially on Fridays.)

While exploring the website at Allen Institute for Brain Science I also stumbled upon a nifty, interactive tool that I'll also probably use in my A&P course.  This FREE tool allows you to view different planes of the brain simultaneously while navigating around the brain.  I imagine that this tool would be fun to use in class to visualize anatomical relationships of the brain as students themselves navigate around and answer their own questions about the general nature of brain structure.

Want to know more?

World's first human brain map unveiled
H. Crawford
NewScientist published online 15 April 2011
[Brief news synopsis with images of applications of the new brain map]

Allen Institute's online MRI explorer
[FREE interactive tool that allows you to explore a human brain MRI to visualize brain structure at different levels that you control.] 

Allen Institute's download page for Brain Explorer 2
[FREE interactive tool that allows researchers to locate biochemistry and/or gene expression at specific brain locations.] 

Monday, April 11, 2011

Looking for a new one-semester A&P textbook?

I'm excited about the recent publication of my latest textbook for A&P students!  Essentials of Anatomy & Physiology is designed for use in one-semester A&P courses. 

Coauthors Gary Thibodeau and Matt Douglas worked closely with me and a very talented team of creative editors and scientific illustrators to produce a textbook that students will love to use.

What?  A text book that students will actually use?!  How can that be?

Let me summarize just two of the many reasons:
  • This book is the most visually oriented textbook in its niche.
    • There are more illustrations than in most other one-semester books, providing students with additional visual help in mastering concepts.

    • Each illustration is carefully designed for maximum learning effectiveness.

    • Most figures include a detailed "walk through" that explains the meaning of image, rather than merely providing a perfunctory title.

    • It includes the Clear View of the Human Body, a bound-in set of transparency overlays that provide a virtual dissection experience for readers as they peel away (or add) layers of the body from either an anterior view or a posterior view.  This experience allows readers to develop a sense of anatomical relationships among body structures.

    • Numerous summary  tables act as graphic organizers to help students see relationships among concepts.

    • We worked hard to get the images and tables close to related text.  This kind of visual integration not as easy at is sounds, requiring several passes at the layout to "get it right" and creatively fit everything together.

  • This text is carefully constructed to be easy to read and easy to raid.  Polls conducted with my students show that most students who use a textbook use some combination of reading chapter sections straight through and simply raiding parts of chapter sections when they need to find something.

    • Even strong readers have some difficulty reading highly technical scientific texts.  We use straightforward, conversational language to communicate difficult terminology and difficult concepts.

    • This text breaks the material down into smaller chapters so that readers do not get overwhelmed and get so discouraged they won't read the book.

    • Our page design uses many levels of bold headings to help students understand the organization of concepts as they read and to find specific concepts when they raid.

    • I worked with reading specialists and ESL teachers to find ways to make the book more accessible to all readers.  For example:

      • We include a significantly larger glossary than most texts in this market. 

      • In-chapter pronunciation guides for all boldface terms used in each chapter.help students master the language of A&P.

    • We provide the meanings of word parts for all boldface terms so that students can start building their skills in understanding scientific terminology

    • A comprehensive outline summary at the end of each chapter visually organizes concepts so that readers can solidify their comprehension of the chapter.

      •  Downloadable audio chapter summaries (included in the included online resources) can be used along with the printed chapter summaries to strengthen understanding even more.
And that's just a small sample of the many unique features of our new Essentials of Anatomy & Physiology. You really do need to see it for yourself!

Want to know more?

If you go to the electronic brochure, you can view a sample chapter, get a list of available ancillaries, learn about the complete online course available with the textbook,  and request a FREE examination copy.

Click the link:  http://my-ap.us/gcH7Jr

Sunday, April 3, 2011

Plaque-fighting bacteria

Have you noticed that the microbiome of the human body has taken off as one of the hottest areas?  Each month, new concepts of how our microbial partners keeps us healthy are revealed.  Last week, we were discussing teeth in my A&P 2 course and I wish I'd had this new tidbit to share with my students:

Researchers recently found that Streptococcus salivarius, one of the microbes in our mouth, can help fight the buildup of plaque on our teeth.  It does so by producing the enzyme FruA, which breaks down carbohydrates in our mouth more efficiently than can the bacteria that form plaque biofilms.  Thus, the plaque-forming bacteria are robbed of their nutrients.

I'll bet S. salivarius will become popular as an oral probiotic.  And its discovery may help us find better ways to manage our mouth's ecosystem to promote good health.

Want to know more?

Inhibition of Streptococcus mutans Biofilm Formation by Streptococcus salivarius FruA 
A. Ogawa, et al.
Applied and Environmental Microbiology Vol. 77, March 2011, p. 1572 doi:10.1128/AEM.02066-10, published online January 14, 2011
[Original research article]

Bacterial fight dental plaque
Tina Hesman Saey
Science News Published online April 1, 2011
[Brief summary of the discovery]
Click the image above to access a FREE animation of tooth decay you can use in your course as you explain the process.

Friday, March 25, 2011

Progesterone's action on sperm finally solved

Two recent articles in Nature reveal a mystery that's been puzzling physiologists for a couple of decades . . . how does progesterone signal sperm cells?

The short version of the story is this . . .

Progesterone is released from the cumulus cells that cling to the outside of the zona pellucida surrounding the ovum. This progesterone binds directly to calcium channels in the sperm's plasma membrane to open.  Influx of calcium ions triggers an increase in flagellum activity.  This increased work is needed for the sperm to get through the zona to the ovum.

Progesterone is a steroid hormone and thus usually enters its target cell and activates transcription of a gene.  In this case, however, progesterone instead directly triggers a calcium channel.  It's not even a second-messenger system, but a direct binding to the channel.

Secretion of progesterone by cumulus cells apparently also provides a chemical gradient that helps sperm navigate toward the ovum.

Recall also that calcium influx into the ovum triggered by contact with a sperm cell plays a role in producing changes within the ovum that result in successful fertilization.

I recommend that my students keep running concept lists on recurring themes or actors in story of human biology.  Here's something they can now add to their calcium list.  Now they can see that a calcium gradient is a truly multipurpose tool in the body.  (For more about running concept lists see my-ap.us/hCIA9X)

Want to know more?
Sperm mystery solved: Scientists identify the channel by which progesterone activates sperm to swim toward an egg
M. Scudellari
The Scientist Published online 16th March 2011
[Nice summary of the significance of the discovery]

Female hormone could be key to male contraceptive: Progesterone-sensing molecule that guides sperm to egg offers fertility solution.
E. Callaway
NatureNews Published online 16 March 2011 | Nature | doi:10.1038/news.2011.163
[Summary article outlining the papers published in Nature]

Progesterone activates the principal Ca2+ channel of human sperm
Lishko et al.
Nature  471:387–391 17 March 2011 doi:10.1038/nature09767
[Original research findings]

The CatSper channel mediates progesterone-induced Ca2+ influx in human sperm
Strunker et al.
Nature 471:382–386 17 March 2011 doi:10.1038/nature09769
[Original research findings] my-ap.us/g14eTK
From The A&P Professor archive
New discovery about sperm's ability to swim
K. Patton
The A&P Professor published online Feb 18, 2010
[Summary of new discovery that when sperm enter female tract, proton channels in the sperm head open and the resulting pH drop triggers influx of calcium, which gets the flagella started in the first place.  That darn calcium shows up in every part of this story, eh?]

Wednesday, March 16, 2011

What do tuft cells do?

We've known for a half-century that the lining of the small intestine has a scattering of weird little cells called tuft cells.  They are called that because they have distinctive tufts of microvilli facing into the intestinal lumen.  But what do they do?  We're finally getting to the answer!

A recent article in Journal of Cell Biology outlines confirms some recent discoveries about tuft cell function and extends our knowledge a bit further.

Apparently, tuft cells are secretory cells that produce opioids in the gut.  They are also the only epithelial cells that produce the COX (cyclooxygenase) enzymes needed to produce prostaglandins involved in inflammation and tumor formation.

Some physiologists had previously proposed a sensory role for tuft cells.  Could they be involved in tasting foods in the gut and be part of the signaling mechanism that regulates exocrine and endocrine secretion that controls digestive and metabolic processes?

As we learn more about tuft cells, we are sure to discover a role for them in normal regulation of intestinal function as well as in important pathological processes. 

Want to know more?

A fifth amendment to the intestine's constitution
Ben ShortJournal of Cell Biology 2011 192:706. Published March 7, 2011, doi:10.1083/jcb.1925iti2
[Brief synopsis of the discovery and its importance]

Distinct ATOH1 and Neurog3 requirements define tuft cells as a new secretory cell type in the intestinal epithelium.
Gerbe, F., et al.
Journal of Cell Biology 2011 Mar 7;192(5):767-80. doi:10.1083/jcb.201010127.
[Original research article.  Includes many illustrations, supplements, helps and cross references. FREE full text]

Here's a really nice teaching image from the Gerbe et al. article, which complements Figure 25-18 in the Anatomy & Physiology 7/E textbook:  my-ap.us/hmdFub (includes downloadable PowerPoint slide)

Here are all the PowerPoints available with the Gerbe et al. article: my-ap.us/gKY7ZG

Chemosensory Perception in the Gut 
Hofer, D., et al.
Physiology February 1999 vol. 14 no. 1 18-23  
[Article proposing sensory function of tuft cells; FREE access to full text/PDF; nice images]


Saturday, March 12, 2011

More study tool slides

In a recent post, I briefly discussed some presentations that I do regarding using Running Concept Lists and Concept Maps to learn anatomy and physiology concepts and how they relate to one another.  I posted links to slides, narrated YouTube videos of brief versions of the presentation, and related study tip pages in my Lion Den website for students.  As promised, this week I'm posting links and short descriptions of four more presentations that may help your students succeed in A&P.

Want to present your own version of any of these study tips? Perhaps embed parts of them into your own presentations? You are welcome to use the slides, which can be found in the Lion Den Slide Collection.  (To use the slides, you'll need the password for downloading them.  Just fill in the form to get the password if you don't already have it.)

Don't forget . . . when using the direct links below, you need to have the super-secret, magic password ready!

In an upcoming post, I'll let you in on some secrets for creating some additional time with you students so that you can cover these study tips without sacrificing "content time" in your A&P course.

Previously described slides available in the Lion Den Slide Collection:

More Slides also available in the Lion Den Slide Collection:

Flash Cards: Reducing Your Study Time 
Some practical tips for using study cards to reduce your study time and get a solid foundation in learning any topic. This video also includes some surprising advanced techniques that show how to use flash cards to also learn higher-level thinking in any subject. Includes discussion of the Leitner system (plus Patton's adaptation of the Leitner system), color codes and symbols, using cards to learn processes and ordered structures, and using cards to build concept maps (mind maps).
Muscle Names Have Meaning
Learning muscles is hard enough without dealing with those crazy convoluted Latin names. But if you pay attention to those names, you'll find that they are actually phrases that help you find the muscles AND help you to remember them in the long term. Find out how this works . . . and where to find lists to help you figure out the meaning of common muscle names.
Exam Strategies
Proven strategies for success in taking tests and exams. What you can do before, during, and after an exam to improve performance in your anatomy and physiology course.
Learn from Your Mistakes: TEST ANALYSIS 
How do you effectively "go over" your tests or exams? Learn how to analyze your tests to see what went wrong and how to fix it.

Don't forget that your students can keep up with all these study tips (and more) on their own by subscribing to my blog The A&P Student.

I have some handy (and bizarre) bookmarks giving students information about The A&P Student blog that you can distribute FREE to your classes!  Just go to my bookmark request page to get bookmarks for your students now.

    Friday, March 11, 2011

    Antibodies work INSIDE virus-infected cells

    You already know that we use antibodies in several ways to combat infection in our immune system.  They bind to pathogens, they activate complement, you know the drill. Well, here's another bullet point to add to your antibody slide: we've found a new intracellular role for the antibody.

    Researchers have recently shown that antibodies can attach to a virus, which then enters a host cell where a molecule called TRIM21 quickly binds at Fc on the IgG antibodies.  By ubiquitin ligase activity, TRIM21 targets the virus's proteins for destruction by the proteasome.

    Click here for an awesome animation that shows all this violent destruction in a simple, dramatic way. Your students will love this animation, because the proteasomes' rapid and total destruction of the virus is so amazing to watch.  And it's a good opportunity to emphasize the importance of the proteasome in the cell. 

    Not only does this observation give us a new intracellular role for antibodies, it also highlights a new and important strategic link between innate immunity (TRIM21/proteasome action) and adaptive immunity (antibodies).

    Want to know more?

    Antibodies mediate intracellular immunity through tripartite motif-containing 21 (TRIM21)
    Donna L. Mallery, et al.
    Proceedings of the National Academy of Science November 16, 2010 vol. 107 no. 46 19985-19990
    Published online before print November 2, 2010, doi: 10.1073/pnas.1014074107
    [This is the original paper, available open access]

    Read this shortened evaluation highlighting the key findings:
    Koch D, Sawtell N: 2010. F1000.com/6381958

    Come Inside
    R. Grant
    The Scientist Volume 25 Issue 3 Page 58 2011-03-01
    [Quick and easy summary, including that awesome video]

    AntibodyBy the way, I love those movies showing miniaturized submarines exploring the inside of the body . . . and this reminds me of the SyFy thriller Antibody with Lance Henriksen and Robin Givens.  Yes, it's a hokey movie, but I like the scenes showing the immune cells attacking the miniaturized sub.

    Monday, February 28, 2011

    Prezi practice practicals

    In my blog The Electronic Professor, I recently wrote about the Prezi alternative to PowerPoint presentations.

    In a nutshell, Prezi creates large, complex sets of information that you can zoom into either at will or in a preplanned way.

    As I was exploring around the Prezi presentations that have been made public, I found a great idea . . . why not use Prezi to create practice lab practicals?

    My students always find it hard to get ready for practicals.  Obviously, part of the issue is the massive amount of content that we ask them to learn.  But, perhaps more imporatantly, it's hard for them to imagine the kinds of questions that they are likely to get. We set up "practice practicals" in our open lab when we can . . . and that helps a lot.  But wouldn't it be great to have an easy to access online place our students can practice for their praticals?

    Well, Rob Swatski at the York Campus of Harrisburg Area Community College (York, PA) has already cracked this egg!

    Take a look at his Virtual Lab Exam for muscles in A&P 1.

    You have to start clicking around and get the feel for how this practice lab practical is set up . . . but once you have the hang of it, it's amazing.  You can see how students can practice the content and also get a feel for EXACTLY the kinds of things they'll be asked to do on their practical.

    Another idea that Rob came up with is shown in this presentation that introduces the microscope.  Rob uses the particular characteristics of Prezi to full advantage to produce a resource that is useful for both teaching and learning in the A&P lab.

    Imagine how useful this sort of thing can be for
    • online tests and quizzes for labs
    • exploring large, complex anatomical structures in a lecture class
    • virtual dissections
    • student presentations
    • zooming in on tissues or bone markings while teaching histology
    Let's hear YOUR ideas!

    Thursday, February 17, 2011

    Concept Lists and Concept Maps

    I've recently posted two new videos that help students learn A&P to my YouTube channel.

    You are welcome to use them in your course by linking to them or by embedding them in your website, LMS (learning management system), or PowerPoint presentation.  Or you can just keep them in mind when students come to you looking for study tips.  Or they may just spark some ideas of your own!

    Concept Lists - A Powerful Study Strategy 
    Running concept lists are a great way to build up what you are learning layer by layer, while at the same time learning relationships between different concepts. If you run your concept lists faithfully, you will also have a handy "personal encyclopedia" of concepts and how they are related.  (Closed Captioned)

    The Concept Lists video is also embedded in one of my Lion Den Study Tips & Tools pages entitled Concept Lists.

    Concept Maps - A Learning & Study Strategy 
    Concepts maps (mind maps) help you understand relationships in human anatomy and physiology in ways that deepen understanding. This video summarizes what a concept maps is, how to make and use one, and outlines some examples of different styles of concept maps.  (Closed Captioned)

    The Concep Maps video is also embedded in one of my Lion Den Study Tips & Tools pages entitled Concept Maps

    Want to present your own version of any of these study tips? Perhaps embed parts of them into your own presentations? You are welcome to use the slides, which can be found in the Lion Den Slide Collection.  (To use the slides, you'll need the password for downloading them.  Just fill in the form to get the password if you don't already have it.)
    When using the direct links, you need to have the super-secret, magic password ready!

    Want more slides? More study tip materials to share with your students?  In an upcoming post, I'll be sharing a few more, ok? 

    Don't forget that your students can keep up with all these study tips (and more) on their own by subscribing to my blog The A&P Student.

    I have some handy (and bizarre) bookmarks giving students information about The A&P Student blog that you can distribute FREE to your classes!  Just go to my bookmark request page to get bookmarks for your students now.

    Thursday, January 6, 2011

    Lion Den Slide Collection

    As you think about getting started in a new semester, you may find that sets of FREE animated slides might help you spice up your classroom presentations.

    For the last several years, I sent a set of hundreds of slides from my Lion Den site for students to anyone who donated to keeping that site up and running.  But starting in this new year of a new decade of a (relatively new) century, I'm now opening up the "secret vault" for anyone who wants them.  And promises to use them for good and not evil.

    If you go to the Lion Den downloads page and join the Lion Den, you'll get acccess to all the slide files.

    Once you are in the download location, you can access the original set of slides in the folder marked  Lion Den Slide Collection Version 1.0. Newer and updated slide collections will be available in the folder Lion Den Slide Collection Version 2.0.  You can follow the links to the folders to see what's there, but you cannot download any of the slide sets until you fill out the form and get the super-secret password.

    You can preview some of the slides by going to the Lion Den slide page.  However, not all the slides in the Lion Den Slide Collection are posted on that website, the slides are posted individually (not in sets), and they are in "slide show" format (which may not be fully editable by you).  The slide sets in the downloadable collection are in fully editable .ppt or .pptx format.  It's much easier to go to the Lion Den download page, join the highly-classified-super-secret membership roster and download the sets of slides.

    All the slides can be freely used (and adapted) for noncommercial educational purposes (see the license embedded in the Notes section of each slide).

    As the User Manual states, these slides are not necessarily as detailed (or as simplified) as you would like to use in your own presentation.  But because they are editable, you can change that, right?  Also, some of these slides were originally intended for a particular purpose (such as introducing a topic that will be explored more fully later).

    Another thing to remember is that the slide sets are not meant to be a complete set of slides covering all topics of A&P.  In my classroom, I use a lot of images from the textbook (provided by the publisher).  The slides in the Lion Den Slide Collection are meant to be supplemental slides.

    Keep in mind that the slide sets are NOT created by a professional graphic artist . . . just old Kevin hacking away in PowerPoint.  So they may not be as slick as some slides you've seen.

    All the slides are in PowerPoint-compatible files.  The newer slides are in the newer XML PowerPoint format (.pptx).