Monthly Archives: May 2015

Anti-Vax Troll

I got some interesting news today…

Apparently, I’ve earned the rank of ‘troll’ from some element of the Anti-Vax movement.

That’s nice of them. Find me here – and check for yourself while you’re at it.

Screen Shot 2015-05-18 at 11.11.01 PM


Posted by on May 18, 2015 in Uncategorized


Sweet Urine

Diabetics often secrete glucose into the urine. This is not due to any intrinsic defect in the kidney or its function, but relates to the maximum amount of glucose that the kidney can actively reabsorb from the filtrate.

Because (uncontrolled) diabetics often have blood glucose levels higher than unaffected individuals, and because glucose is small enough to pass through the glomerulous and into the nephron, a large amount of glucose can be found in the filtrate. However, the nephron does have transporters to reabsorb glucose in the proximal convoluted tubules. In unaffected persons, these transporters are sufficient to completely capture glucose before it is lost as urine. The high sugar concentrations of diabetics can surpass the capacity of these transporters to rescue ALL of the glucose in the filtrate, thus allowing some to pass into the urine.

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Posted by on May 11, 2015 in Uncategorized


Flow Rate

I received an extra credit essay from one of my students based on a question from the textbook that I had to do a little modeling to understand. The question was one about patients with atherosclerosis that could be explained using Poiseuille’s Law. This Law describes the relationship between the flow rate, pressure, radius and viscosity of a liquid flowing through a vessel.

Basically, it is presented as:

Flow Rate = change in Pressure * pi * radius^4* Length of the vessel * viscosity

.                                                                    8

The question asks, ‘why symptoms of myocardial ischemia do not usually occur until ~75% of a vessel has been occluded.’

The easy answer is that that is the cutoff after which the amount of blood required to provide Oxygen sufficient for the heart’s metabolism is insufficient. However, this can be visualized qualitatively simply by graphing the equation. To do this, I made up a quick spreadsheet and just plugged in ‘1’ for all the variables, then solved for the flow rate. From here, I simply plugged in fractions into the radius variable.

Here’s the raw data:

Screen Shot 2015-05-08 at 5.00.16 PM

1.00 – 0.75 (i.e. a 75% blockage) = 0.25 is the number from the question. Here’s the analysis:

Screen Shot 2015-05-08 at 5.02.20 PM

Note how the Flow Rate has dropped to essentially ZERO when the radius is occluded 75%.

There may be more to this, but I think that just looking at this analysis of the equation answers a lot.

ps – I just spent a hell of a lot of time and effort messing around in the terminal of my mac changing the screen capture file type all to realize that it wasn’t my mac that was the problem at all – I simply was not using the largest image type available in wordpress and then tried to scale up my image after it was inserted – don’t do this. You lose all of your image quality.

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Posted by on May 8, 2015 in Uncategorized


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Oooooooo! Reeeeenal Physioooooology!!! Spooky!

OK, please forgive the cheesiness of this post – and I do hope that it will come through clearly enough to read. Unfortunately, the type did not copy as cleanly as I would have liked.

Check out the comic and then consider the questions that follow.


1. How can Bedelia and Nathan have similar conditions, but dissimilar symptoms?

2. Why does Sylvia harp on so about Bedelia’s sex life?

3. Nathan looks pretty exhausted. Why is he feeling so weak? What do you expect is happening to him to cause his symptoms?

4. Placing a catheter may help Nathan today, but what options does he have for long term treatment?


Posted by on May 6, 2015 in Uncategorized


You are now leaving Twin Peaks, population 51,201

Twin-Peaks-logoTomorrow is the last day for my Microbiology class this Spring.

We’ll be having our last exam -on immunology- and moving on to greener pastures. I hope my students have learned something from the experience and will perhaps also be open to the joys of Slow-Moving Supernatural TV Dramas and Bad Horror Flicks.

As I’ve been hinting at lately, perhaps next semester I can move on to revisiting Northern Exposure – something to think about if you’re considering taking my pathophysiology class this summer.

By the way, Sunday is Mother’s Day. Take a moment to remember all the great mothers out there…




No - wait. He's not a good mother at all.

No – wait. He’s not a good mother at all.

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Posted by on May 4, 2015 in Uncategorized


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Pathophysiology Extra Credit -Consolidated

I’m consolidating the questions that have been submitted so far for the last exam on renal pathophysiology. Feel free to comment on any of these questions, ask for clarifications, or add new ones. I’ll consider any well-stated, quality questions submitted before noon Saturday.

What is the physiological reason the kidneys play a crucial a role in controlling blood pressure. Is it….

A. If your blood pressure is too high it is not good for your heart
B. The angiotensinogen renin system is the best way  <<- I’ve got to think of an alternate answer here
C. The loop of henley can’t withstand the pressure
D. sufficient pressure is required to filter material from blood through the nephron

Answer D

Which lab test is most commenly used as a screening measure of renal function?
A) BUN (Blood Urea Nitrogen)
B)Blood Test
C)Serum Creatine << Corrected to Serum Creatinine
D) Sodium Urine output

[Both BUN and Serum Creatinine are useful, but BUN is more likely to fluctuate following meal]

Which type of renal failure is caused by the obstruction of urine output from the kidneys?
A)Prerenal Failure
B)Postrenal Failure
C)Intrinsic Renal Failure
D)End Of Life Renal Failure

A patient recently had a computed tomography (CT) and was diagnosed with Polycystic Kidney Disease. What had the doctor seen that indicated that diagnoses?
A)Renal calculi in the kidneys
B)Fluid-filled sacs in the tubular structures of the kidney
C)Malignant tumor
D)A rapid decline in kidney function

[good question, I like this one]

The clinical manifestations of glomerular disorders generally fall into one of five categories.
– acute nephritic syndrome
– rapidly progressive glomerulonephritis
– nephrotic syndrome
– asymptomatic hematuria or proteniura
– Chronic glomerulonephritis

There are also several disease that cause secondary glomerular kidney disease such as systemic lupus, diabetes, and hypertension.

1.) Acute nephritic syndrome evokes an inflammatory response in the glomeruli and results in extracellular fluid accumulation ad edema because of a decreased GFR. What clinical manifestations would a nurse observe?

A. bradycardia, polyuria, dehydration
B. Hematuria, oliguria, hypertension
C. Decreased sensation in the lower extremities
D. None, this typer of Glomerular disease goes unnoticed by the patient and the provider.

Answer: B

2.) The glomerular membrane acts as a size-specific barrier through which filtrate from the blood must pass. One type of glomerular disease that affects this function is know as nephrotic syndrome. What are some clinical manifestations a nurse would observe?

A.) hematuria, oliguria, hypertension
B.) Hyperalbuminemia, dehydration
C.) Proteinuria, hypoalbuminemia, generalized edema
D.) None, thype of glomerular disease goes unnoticed by the patient and the provider.

Answer: C

3.) Rapidly progressive glomerulonephritis is a syndrome characterized by signs of sever glomerular injury, is rapidly progressive and does not have a specific cause. What is one disease associated with this type of glomerular disease?

A.) Staphycocci infection
B.) diabetes
C.) Goodpasture syndrome
D.) kidney transplant

Answer:  C

[although rare, Goodpasture syndrome is interesting because of its rapid progression and clearly diagnosable immunohistochemistry]

4.) Asymptomatic glomerular disorders are not generally recognized or brought up to healthcare providers, and many times remain undiagnosed. What are two clinical signs associated with asymptomatic glomerular disorders that may be seen in a patient even though they have no other complaints?

A.) Hemituria and proteinuria
B.) Itchy skin and watery eyes
C.) Generalized edema and toenail fungus
D.) Constipation and anxiety

Answer:  A

[why is it that the patient is not seeing the hematuria?]

5.) many immunologic, metabolic and hereditary diseases are associated with glomerular injury. With many of these diseases glomerular injury is a secondary manifestation. What is an example of this type of disease.

A.) Diabetes mellitus
B.) Hypertension
C.) Exema
D.) Both A and B

Answer:  D

1.Painful or difficult urination is called?

Answer B

2.A condition in which very high levels of protein are lost in the urine and abnormally LOW LEVELS OF PROTEINS are present in the blood
Answer A

[straight from my own extra credit question – how can I not like it?]

3.Very low urine production
A. Proteinuria
B.Renal dysplasia
C. oliguria
D. Hydronephrosis
Answer C

[I like this one too]

4.In renal _____, the kidneys do not develop to normal size.
A.Potter syndrome
B. hypoplasia
C. dysplasia
D. multicystic
Answer: B

[and this]


Posted by on May 4, 2015 in Uncategorized


Autism’s False Prophets Questions – Part II

vaccines-save-livesA second installment in questions referring to Paul Offit’s book, Autism’s False Prophets. These questions mark the last of those we will cover for this book.

Autism’s False Prophets                                                                           Name:

Chapter 11 Questions

A Place for Autism

  1. What evidence is there for a genetic cause of autism?
  1. Other than genetics, what other things may cause autism?
  1. Who is the Autism Diva, and where did she come from?
  1. Who is Peter Hotez, and how did he get involved in the public conversation about autism?
  1. What does Peter Hotez think is the hardest part of being parent to an autistic child?
  1. What does Kathleen Seidel say is a problem about the way that doctors and scientists see the world?
  1. As always, at the end of a book like this, I like to ask for your feedback on whether you found this book important, what it might lack, and whether you think that I should keep using it in future classes.
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Posted by on May 3, 2015 in Uncategorized


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