Thursday, October 5, 2017

Q21. Mouse Breeding Basics



How much do you know about mouse breeding?   Might be useful one day to know a few fun facts!
Here are some questions you ought to know the answer to.... (and if you forgot - links to useful online references are provided)





1.  Mouse pups: at what age does...

  • The milk spot disappear
  • Hair first appear
  • Ears start to come away from head
  • Teeth erupt
  • Eyes are fully open
  • Eat solid food
Check HERE if you need a reminder

2.  Timed breeding.  How would you time breeding without the use of drugs?   ( there are good summaries HERE  and HERE)

3.  If you need to superovulate to produce many eggs (eg for embryo freezing) the protocol is...
  • Take group housed female mice aged _______ days
  • Inject 2-5 IU PMSG between ___________(time of day) on day 1.
  • Inject 2-5 IU HCG ________   hours later on day _____
  • Mate with stud (8 weeks old individually housed)_____________(when?)
  • Ovulation occurs __________ hours later.
(And HERE is the protocol)

4.  Estrus Cycle: visual external characteristics (ie vaginal opening appearance) 
  • What distinguishes proestrus from estrus? 
  • Metestrus from Diestrus?
5. Estrus Cycle: Vaginal smears - 
  • What distinguishes proestrus from estrus? 
  • Metestrus from diestrus?
A really nice review for questions 4 and 5 can be found HERE

6. Early Pregnancy Diagnosis
  • Ultrasound can identify pregnancy as early as Embryonic Day ___  (assuming day following mating is Day 0.5)  Reference 
  • Weight change can identify pregnancy as early as day ED_____   Reference
And here are a few easy ones...
7. Delayed implantation generally occurs when ________________________________ 
8. For breeding, always add the female/male to the female/male's cage
9. Gestation generally lasts between ___ and ____ days
10. B6 mouse pups should weigh approximately _____grams on weaning at 3 weeks.


Monday, September 18, 2017

Q20: Pneumocystis: clinical implications and diagnosis



From IAhealth.net





For many organisms the information I learned decades ago is still largely correct (except for a tendency to change the name and then change it again!)  However for Pneumocystis this is not the case.  So here's a little quiz to see how up to date you are on Pneumocystis...

1. True/false. Pneumocystis was first discovered in 1909 and was thought to be a stage in the life cycle of Trypanosoma cruzi
2. True/false.  Pneumocystis is only a clinical problem for immune-suppressed animals
3. True/false.  Pneumocystis species are not host specific and they affect a wide range of mammalian species
4. The following diagnostic methods for rat pneumocystosis are the most sensitive:

  1. PCR of an oropharyngeal swab or wash
  2. PCR of feces
  3. Serology 10-20 days after the infection
  4. All of the above
  5. None of the above
5. In rats, Pneumocystis was previously known as __________and the species name is/are _______. In mice the species name is P.___________
6. Pneumocystis is intra/extra cellular, is classed as an  ___________________ and does/does not respond to antifungal treatments
7. In people, the Pneumocystis species name is P.______________, the infective stage is the _____ and transmission is by the ________ route
8. True/false.  In people, Trimethoprim/sulfa is the usual treatment.
9. The course of the disease in rats is acute/chronic and peak  disease occurs ____wks after infection
10. Pneumocystis can/cannot reliably be cultured in vitro
11. True/false. Pneumocystis cysts can survive freezing at -80C, but are susceptible to most common disinfectants.
12. The usual stain for identification of Pneumocystis in the lung is __________________

References: 
Peter Walzer in J eukaryot microbiol 2013 60(6)
Procop et al in J Clin Microbiol 2004 p.3333-
Menotti et al PLOS 1 8(4) April 2013
Kim et al experimental and therapeutic medicine 2014. 8:442-446
http://www.criver.com/files/pdfs/infectious-agents/rm_ld_r_pneumocystis.aspx (accessed 9/2017)
http://dora.missouri.edu/rats/pneumocystis-carinii-formerly-known-as-rat-respiratory-virus/






Tuesday, September 5, 2017

Q 19. Rabbit Bacterial Diseases.


This week we'll do a more 'traditional' lab animal species. There's a lot to know about rabbits, but here are some questions on bacterial infections to get you started...

  1. E coli.  True or False?
    1. E coli can be identified in normal rabbit feces and E coli overgrowth often results secondary to another infection
    2. Enteropathogenic strains of E coli can be diagnosed by serotyping and biotyping  in addition to PCR.
    3. PCR identification relies upon the abc gene that codes for intimin
    4. Disease manifestation is highly dependent upon serotype: O15:H is highly pathogenic whereas O103:H2 and O123 are not.
    5. Pathogenic strains typically exhibit attaching and effacing pathology.
  2. Treponema paraluiscuniculi
    1. Was formerly known as__________________
    2. Is closely related to T pallidum the cause of human __________ (disease)
    3. Disease is usually transmitted during___________
    4. The  ____ genes are primarily responsible for virulence.
    5. Diagnosis can be confirmed from a microscopic sample stained with_____________
  3. T paraluiscuniculi (True or false?)
    1. Antibodies to T pallidum and T paraluiscuniculi cross react
    2. Antibodies to one organism provides protection against the other 
    3. The lesions are generally restricted to mucocutaneous junctions and regional lymph nodes and can persist for many months 
    4. Following infection, seroconversion follows within 3 weeks 
    5. Positive serology in the absence of lesions indicates complete recovery from the disease
  4. Tyzzers Disease 
    1. is caused by _________ formerly known as ___________
    2. Most infections are subclinical/severe.
    3. During an outbreak,  there is typically high mortality in ___________ (age group)
    4. The most consistent organ infected is the liver; cecum/intestine; heart (pick one)
    5. Infection is generally via ingestion of _______
    6. True or false?  Latent infections exist, and clinical disease can result from stress
    7. _________ (another species) are highly susceptible to Tyzzers disease and have been used to diagnose latent infections
    8. True or false? PCR diagnosis is complicated by cross reaction with non-pathogenic bacteria.
  5. Enterotoxemia in rabbits 
    1. Is caused by the Clostridial organism ___________
    2. The toxin responsible for disease is neutralized by antiserum to _______(toxin) from this organism __________
    3. Enterotoxemia is most likely to follow changes such as ________________(give examples).  Mortality is highest in  ______________ 
  6. The most common bacterial infection in rabbits is _______ caused by ________________
    1. The most common clinical form of this disease is _____________
    2. This organism is also the primary cause of ________, ________,__________, __________ in rabbits
    3. Serotypes __ and __  are most commonly associated with disease in rabbits
    4. Infection is usually acute/chronic
    5. Humoral immunity protects against ____________ but not _____________
    6. Culture diagnosis based on colony morphology can be accomplished by incorporation of _______ , which suppresses most other likely flora,  into the growth medium
    7. A single serological test is sufficient to assure negative status. 
Reference: the 'blue book' "The Laboratory Rabbit, Guinea Pig, Hamster, and Other Rodents" Elsevier 2012.

Answers are now posted HERE (or click on the answers link in the right sidebar)


Monday, August 21, 2017

Q18: What do you know about bats? (yes, bats!)

Our laboratory animals can certainly be unusual, but perhaps one of the strangest animals we look after are the various species of bats.   Today's questions are on bats in the laboratory...

1. Classification:
  • Which order (from the Greek 'hand' and 'wing' do bats belong to? _________  
  • There are over 1300 known species of bats. Big Brown Bats and Little Brown Bats are common in the United States. What is the genus and species of big and little brown bats? 
  • The big and little brown bats are part of the bat family___________________
2.  Bats in North America are a reservoir species for rabies, and have surpassed dogs as the major source of human rabies cases in North America.  
  • Rabies virus belongs to the family_________ and genus ____________________
  • All personnel working with bats or bat tissues should be vaccinated against rabies. Initial rabies vaccination consists of single/multiple (pick one) doses.
  • True or false?  Following potential exposure, vaccinated individuals do not need post exposure prophylaxis.
  • True or false? Post exposure prophylaxis may consist of more than one vaccine dose and immune globulin
  • True or false?  The incubation period for rabies in bats may exceed 13 weeks                            
3. Biology
  • Although some species of bats may suck blood, eat fish or small mammals, or eat nectar or pollen, the vast majority of bat species feed on __________
  • Bats are nocturnal/diurnal/crepuscular and sleep in ________ 
  • True/false  They live many times longer than other mammals of the same size
  • The gestation period is ___________ and newborn bats are precocious/altricial
  • True/false  Some bats hibernate and migrate seasonally 

4. Bats use a unique method to locate their prey_____________  This, together with study in the wild for evidence of ___________constitute 2 major areas of research using bats.

5. Over 200 viruses have been detected in bats and there is some evidence that some bats can remain asymptomatic while harboring viruses that can infect humans.  In  addition to rabies virus, bats are increasingly being linked with emerging human diseases.  
  • True/false  In addition to rabies, bats are suspected to have acted as reservoirs, either directly, via fomites/vectors (such as partially eaten fruit), or via intermediate hosts such as carnivores (e.g. ferrets, raccoon dogs) perissodactyls (e.g. horses) or artiodactyls (e.g. pigs and camels)  for the following diseases:
    • Rabies-related viruses such as Australian bat lyssavirus
    • Paramyxoviruses such as Hendra virus and Nipah virus
    • Coronaviruses such as SARS/MERS
    • Filoviruses such as Ebola virus and Marburg virus
    • Alphaviruses such as Venezuelan equine encephalitis virus 
6. True/false. Wild caught big brown bats may be infested with mites, ticks, bugs and various endoparasites and should be treated for parasites on arrival in the laboratory. 
  • True/False  Ectoparasites have been implicated in the transmission of white nose syndrome (Geomyces destructans), which is causing rapid destruction of small brown bat populations in North America
ANSWERS POSTED HERE or click on the answers 11-20 on right sidebar


Tuesday, August 8, 2017

Q17: Coat Color Nomenclature

Picture: gengennews.com


It's time for some new questions, and this week I'm going to put up a few questions that test your knowledge of coat color nomenclature.  It's a confusing topic, and for many people (including me) it requires a number of iterations before it starts to sink in. So if you're thinking about studying for boards next year, it's never too soon to start thinking about it. Or if you just want to see if you can remember what you once knew... go right ahead!

I'm going to make it relatively easy for you on this first post...




 Considering the following...
A. Nonagouti locus,  a
B. Tyrosinase-related Protein 1 locus,  Tyrp
C. Tyrosinase locus,  Tyr

1. Which is responsible for:
- black/brown color?
- albinism
- agouti coat

2. Regarding the nonagouti gene,
- which is dominant, agouti or nonagouti?
- what is the banding pattern of colors along the hair for agouti?
- what are the colors and banding pattern in a cinnamon mouse?
- is a DBA mouse agouti?

3. Regarding nude mice (OK I know they don't have hair, I digress)
- What is the gene/allele symbol for a nude mouse?  Expand the gene symbol into words...
- What is the developmental abnormality that results in the immune deficiency in nude mice?
- Do they have normal B and NK cells?
- What happens to their immune deficiency as they age?

4. What color is this mouse?
- a/a Tyrp1b/Tyrp1b Tyrc/Tyrc  (please note the alleles should be superscripted, but I can't do that easily on here)

5. What color is this mouse?
- a+/a  Tyrp1B/ Tyrp1b   Tyr C/Tyrc

6. True or false?
- FVB and BALB/c (and other common albino mice) are albino because of a point mutation from a shared ancestor
- Mouse albinism is caused by disruption of the first step in the production of melanin
- The suppression of one gene by another is called epistasis.

7. Which of these gene/alleles are responsible for coat color dilution?
- Myo5a_d
- Mlph_ln
- Lyst_bg
- Kitl_sl
- Kit_W

8.  In Q7, what are the names of the dilution alleles?


Best of luck!  Will post the answers in a week...

Did you know? A group of flamingoes is a flamboyance




Friday, July 21, 2017

Q16: Preparing images for publication and other Photoshop do's and don'ts

Today's post is all about images: how to best use that indispensable tool, Photoshop, without making the kind of errors that degrade your image or make them ineligible for publication. Our questions and answers were provided by Chris Zink, DVM, PhD, Dipl. ACVP, [website: canine sports ], who has extensive experience in preparing publication-quality images.


1. When making a new file, you should set the resolution to: (select one)
a) 72 dpi
b) 240 dpi
c) 300 dpi
d) 600 dpi

Layers menu


2. When working on an image in Photoshop, every time you add something to your image (lines, letters, new images to make composites, etc.) you should open a new layer and perform that action on the new layer. The main reason for doing this is so that:_____________________________________

3. True or false: Photoshop works on a vector system, in which the program memorizes the directions of various lines that are drawn when an image is being made. This prevents the problem of pixellation.



4. Which of the following Photoshop modifications can you ethically make to a photographic image of data that you plan to publish in a scientific journal?
a) Selective cropping
b) Whole-image brightening
c) Cloning
d) Changing resolution without resampling
e) White balancing
f) Changing tint
g) Whole-image sharpening
h) Changing resolution with resampling

5. True or False: Photoshop is an excellent program for creating and editing images

6. The best tool to white balance an image is:

a) Brightness Contrast tool;
b) Levels tool
c) Curves tool
d) Color balance tool





7. When adding text to label images in Photoshop, you should generally use:
A                                                             B
 
A) A serif font
B) A sans serif font

8. True or false? When modifying photographs in Photoshop that you plan to submit to a journal for publication, you should change your image to its final resolution first, so that all of your changes are performed in that resolution.

9. True or false: When modifying images in Photoshop, always record all of the steps you are taking, 

10. True or false:  When you want to save an image that you have been modifying in Photoshop, it doesn’t matter whether you save it as a .tiff or a .psd file – in both cases the image will be saved in layers.

As always, check back next week for the answers!  (Link was temporarily down due to an html near-disaster, but it's back up again now :))

Monday, July 17, 2017

Remembering things... the memory palace and other imaginary objects...

Last week I attended a great workshop on memory - specifically on how to remember things.  I know that this is a topic of perennial interest - even if it's just that you can't remember peoples' names (like me).   And if you took the ACLAM boards exam this past week - congratulations for buckling down to all that studying and best of luck!

So before we get to the memory/mind palace let's talk about a few basics.  I think everyone knows by now that highlighting is a pretty inefficient way to try and commit something to memory.  Ditto reading something through multiple times.  What works is making the brain work hard and pay attention - specifically by thinking about it, testing yourself on the material etc.  That's probably why flash cards work, but only if you really think about the ones you get wrong!  Write yourself questions about the material, close your eyes and see how many facts you can recall from what you just read, even writing summary notes in your own words - it all works better than just reading something.  For more information check out this course from UCSD. I used to write myself notes that were crammed all over the page with boxes, colors, arrows, whatever.  When I came to recall the material I actually visualized the page - which brings me to the first thing I learned in the memory workshop.  Memory is primarily visual.

Because memories are visual,  we were told, you need to actively store them as pictures.  As a kind of
pre-test, we were given a list of 20 objects to remember in their correct order 1 through 20 - not a written list, the instructor read them out loud.   I knew I didn't have a chance of just 'remembering' them so I invented a story in pictures from the words (I can still remember that story and most of the words a week later).  I actually did pretty well in terms of recall (I got 18/20 words in the right order) but didn't do so well on the test because one of the 2 words I missed was early in the sequence so all the other words were one number early... and if I had been asked for word 15 I wouldn't have been able to tell you without recounting the entire sequence ( or not at all because I forgot one word in the sequence).  Which is where the memory palace comes in.

The memory palace allows you to remember the words AND where they sit in the sequence.  How? by associating them with a sequence of objects that you have no trouble remembering.   There are a number of different methods, but the memory palace involves remembering a place you know really well (like your house, your childhood home, etc) and walking through it in a fixed sequence, remembering objects you are familiar with.   You set this "memory palace" in advance and memorize it (not difficult because you already know this place really well).   The example we were given for the 20 objects was to walk around 4 rooms in the same direction and recall 5 objects in each room.   It could be a wall, a toilet, a window, a refrigerator...  you get the idea.   Once that sequence is well established, then you associate your list of 20 words with your objects in the room.  Not just associate, but think of an outrageous and ridiculous association.   Supposing your first memory palace object is a sofa and the object you are trying to remember is cigars - maybe you think of a giant cigar on the sofa, or hundreds of cigars cascading off the sofa, or a monkey smoking a cigar on the sofa...  you get the picture (!).  The effort of thinking of the ridiculous association "fixes" the picture in your brain.  If it's too easy to come up with the association, it will be the one you forget, so work at it.  Repeat this for each object as you walk around the rooms.   Now if you have to recall object 15, you just need to think of the picture association for the 5th object in room 3.  It works, trust me.   I got all 20 (new) objects in the correct sequence on the second 'test.'

Well you might say, this is all great if you have to learn a list of 20 objects, but what if they are NOT
objects?  After all, most of what we might like to learn is not really a grocery list (though come to think of it, having a grocery list in my head might have prevented me forgetting the onions I needed for that recipe last week).  That takes you on to the next stage, which is imagining a picture for something that is not an object.   The example given was names - think of a "sounds like" or picture that brings to mind that name.  For my name, "jewel" would represent "Julie".  So if someone were to want to remember my name, they would picture my face and some amazing jewels ( some nice big diamonds would be good! 😉 ) - perhaps as big as melons...though then they would definitely be fake.  And if a whole group of people needed to be remembered,  then walk around your memory palace and associate the silly face/name combinations with your room objects.

In our profession, there is a lot of rote memorization that might lend itself to these techniques (perhaps nomenclature acronyms or lists of differential diseases).  And failing that, remembering someone's name is definitely a useful skill.   I'm planning on reading more on the subject - lots of books available but this one gets good reviews so it's as good a place to start as any.  If you're taking Boards next year, you might do worse than take in one of these books before you get started on your study journey...