Term of the Day

Colles' Fracture: Fracture of the distal radius with dorsal displacement or angulation of the distal fragment. Typically results from forceful trauma, commonly from falling on outstretched hands. The ulna is unaffected, since it doesn't form part of the wrist joint.

Term of the Day

Comminuted Fracture: A break in which the bone fragments into many pieces. Especially common in elderly people suffering from osteoporosis.

Term of the Day

Marfan's Syndrome: Genetic disorder of connective tissue. Abnormal connective tissue results from a defect in the protein fibrillin, which helps provide scaffolding and structural support between cells. Signs and symptoms include: excessive height, abnormally loose joints, long spiderlike fingers, poor vision, and a weakened heart and blood vessels due to inadequate connective tissue reinforcement. The trait is dominant and carried by the FBN1 gene. For you punk rockers out there, Joey Ramone was diagnosed with Marfan's.

Term of the Day

Duchenne Muscular Dystrophy (DMD): Inherited, sex-linked, recessive, muscle-destroying disease. Females are carriers of the abnormal gene, but the disease almost exclusively strikes males. The gene results in the lack of an important protein called dystrophin, which is crucial for maintaining the structural integrity of the sarcolemma. DMD is typically diagnosed between ages 2 and 6 as previously normal children become clumsy and begin to fall more frequently. The degenerative process progresses from the extremities to the head and trunk. Death comes when the diaphragm and other inspiratory muscles are damaged. Patients rarely live beyond their 20s and die of respiratory failure.

Health Alert

15 January 2009: the Kellog Co. announced that its peanut butter crackers may be tainted with salmonella and consumers should not eat them. The alert affects the Austin and Keebler brands. the problem is the peanut butter produced by the Peanut Corporation of America, which has been linked to an outbreak of salmonella affecting over 430 people in 43 states.

Term of the Day

Pyelonephritis: Infection and inflammation of the renal pelvis and interstitium. It is usually bacterial in nature (E. coli, Proteus, or Pseudomonas being the usual culprits), but viruses and fungi can also be causative organisms. It is more common in women, and urinary obstruction and vesicoureteral reflux are risk factors. One or both kidneys may be involved.

Health News: Poor Sleep Prior to Rhinovirus Exposure Leads to Reduced Resistance to the Common Cold

Poorer sleep efficiency and shorter sleep duration in the weeks before exposure to a rhinovirus are linked to greater susceptibility to the common cold, according to the results of a study reported in the January 12 issue of the Archives of Internal Medicine.

The study sample consisted of 153 healthy men and women volunteers aged 21 to 55. For 14 days, subjects reported their sleep duration and sleep efficiency, defined as percentage of time in bed actually asleep for the previous night and whether they felt rested. The investigators calculated average scores for each sleep variable during the 14-day baseline. Participants were then quarantined, inoculated with nasal drops containing a rhinovirus, and monitored for the development of a clinical cold on the day before and for 5 days after rhinovirus exposure. Clinical cold was defined as infection in the presence of objective signs of illness.

Participants who reported less than 7 hours of sleep were nearly 3 times more likely to get a cold than those with 8 hours or more of sleep, suggesting a correlation with average sleep duration. Participants with less than 92% sleep efficiency were 5.5 times more likely to get a cold than those with 98% or more efficiency, also suggesting a correlation with sleep efficiency.

So, your mother was right -- you need to get plenty of sleep!

Arch Intern Med. 2009;169:62-67.

Term of the Day

Postconcussive Syndrome: A cluster of symptoms that may persist for weeks or months following a cerebral concussion, including: headache, anxiety, irritability, insomnia, depression, impaired concentration, forgetfulness, and fatigability.

Case Study -- A Simple Case of Pneumonia?

O.K. ladies and gents, time to play Dr. House! We'll start with a relatively simple case of pneumonia...

Patient A presents to the emergency room with symptoms of pneumonia, including cough, dyspnea, and hemoptysis. X-ray confirms the presence of diffuse infiltrates in the right lung, and on physical examination, hypoventilation and hypotension are noted. The history reveals that, prior to the pneumonia, the patient had not experienced any respiratory symptoms of any kind. The patient did report, however, that he had been experiencing a mild, stabbing chest pain 10-15 seconds after swallowing food or liquids, and often found it difficult to swallow. He reported that if he "bore down" as if he were defecating, swallowing was usually easier. The problem was worse when he had to eat in a hurry, and he said food sometimes "went down the wrong pipe" producing coughing fits. He had been experiencing this for months, and had tried managing his own symptoms using Maalox, without any real success -- the problem seemed to be getting worse. He reported a particularly bad episode of regurgitation and coughing the day before his breathing problems started.

What kind of pneumonia does A have? Is pneumonia the real underlying problem here? If not, what is/are the likely diagnosis(es)? What test would you order next? What "sign" would you be looking for on this test?

Term of the Day

Cor Pulmonale: Right ventricular enlargement (hypertrophy, dilation, or both) secondary to pulmonary hypertension. Increased afterload (pressure in the pulmonary trunk) leads to chronic pressure overload in the right ventricle, thus increasing the work it must do. The right ventricle ultimately fails when pulmonary artery pressure equals systemic blood pressure.

Term of the Day

Furuncle: The medical term for a "boil" -- an inflammation of the hair follicles. It may develop from pre-existing folliculitis that spreads into surrounding dermis. The causative microorganism is usually S. aureus.

Term of the Day

Acsites: Accumulation of fluid in the peritoneal cavity, which reduces the amount of fluid available for normal physiologic functions. Cirrhosis of the liver is the most common cause, but other diseases associated with ascites include: heart failure, constrictive pericarditis, abdominal malignancies, nephrotic syndrome, and malnutrition.

Pathophysiology News -- Vitamin Supplements and Cancer Prevention

Bad news for those of you counting on vitamin supplements (especially antioxidants) to reduce your cancer risk. A new study to be released in the 7 January 2009 issue of the Journal of the National Cancer Institute indicates that vitamin C, vitamin E, and beta carotene do not help prevent cancer or reduce cancer mortality. The study followed 7627 women who were cancer-free at the outset of the experiment. Control subjects were given placebos; one experimental group was given 500 mg of vitamin C daily; another experimental group was given 600 IU of vitamin E every other day; and a third experimental group took 50 mg of beta carotene every other day. The average duration of treatment was 9.4 years.

Six hundred twenty-four women went on to develop invasive cancer, with 176 of them dying. None of the antioxidants performed any better than the placebo in reducing total cancer incidence. Neither was there any statistically significant difference among the 4 groups in cancer mortality. Combined use of all three antioxidants was also found to have no effect.

Term of the Day

Alkaline Reflux Gastritis: inflammation of the stomach caused by reflux of bile and pancreatic secretions (proteolytic enzymes and bicarbonate-rich fluid) that disrupt the mucosal barrier of the stomach. It is one of the risk factors associated with gastrectomy or pyloroplasty. Symptoms include nausea, bilious vomiting, and epigastric pain that worsens after eating and is not relieved by antacids.

Welcome to the Anatomy and Physiology Student's Forum!

I'm Scott Boulding, and I have been a professional Anatomy & Physiology, Pathophysiology, and Biology teacher for some years now. The idea for this blog was born of my own students' struggles with and attempts to master the large volume of challenging material these courses represent. One of them aptly described the learning process as akin to "taking a sip of water out of a fire hose!" So, I decided to create an online forum in which they could share ideas, ask questions, provide useful links, exchange study tips, and so on. Soon realizing that such a resource could benefit other students from the high school through the grad school levels, I decided to make this blog available to the general public. If you are taking Anatomy and Physiology, Human Biology, Gross Anatomy, Human Physiology, or Pathophysiology, this blog is for you. If you are a teacher of any of these courses, you are also welcome to provide comments, feedback, and answers to student questions. Everyone with an interest in these subjects is welcome here!

In addition to the questions and comments threads, I will also be posting key terms and their definitions daily (think of it as your Anatomy and Physiology Word-a-Day calendar), as well as discussing and explaining a different A&P concept each week. Feel free to add to the discussion, expand upon the information, ask questions -- whatever will be useful to you as you try to learn the material! From time to time, I will also throw in some short quizzes to help you test your knowledge and understanding

If you feel like you need more intensive tutoring, you can also find me at www.globalscholar.com or at http://imlive.com/waitingroom1ms.asp?hostnick=DocentisMaximus. If you're in the Tampa Bay area and want some live, one-on-one tutoring, just drop me an email (sboulding@tampabay.rr.com), and I'll be happy to arrange a meeting that is convenient for both of us.

In the meantime, enjoy the blog; I hope you find it helpful. As with anything, you'll get out of it what you put into it -- trite, I know, but true, nevertheless. Good luck with your studies!

Scott Boulding