bio tech

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  1. The interaction of the      mammalian brain and immune system is:

  

only a defensive   response to pathogens

 

always a   destructive autoinflammatory pathology

 

sometimes a normal   part of development

 

always either a   response to a pathogen or a destructive autoinflammatory pathology

QUESTION 2

  1. The brain is surrounded      and protected by the blood-brain barrier (BBB), a border of endothelial      cells which separates the blood from the fluid surrounding the central      nervous system. Testosterone is produced in the gonads, so how can it      affect development of the brain?

  

Testosterone cannot   cross the blood-brain barrier and must direct cells lining the BBB to secrete   their own signaling molecules to influence the brain.

 

Steroid hormones   are relatively small and lipophilic, so testosterone readily crosses   the selectively permeable blood-brain barrier and   acts directly on androgen receptors (or is locally converted into estradiol   and acts on estrogen receptors)

 

The blood-brain   barrier only prevents the migration of cells; anything soluble in the blood   fluid can easily cross it.

 

Testosterone does   not do anything to the brain.

QUESTION 3

  1. Increased microglial      phagocytosis in response to endocannabinoid (eCB) signaling was observed:

  

throughout all   regions of the brain

 

only in the   amygdala

 

throughout the   entire body

 

the prefrontal   cortex

QUESTION 4

  1. For what purpose did the      authors use an antibody against ionized calcium binding adaptor molecule 1      (Iba1)?
         How did they determine which cells were engaged in phagocytosis?

   

QUESTION 5

  1. Staining for      proliferating cell nuclear antigen (PCNA) enabled the authors to determine      the cells the microglia were engulfing were recently divided cells. Since      microglia are known to phagocytose dead or apoptotic (dying) cells, the      researchers looked for a specific marker of apoptosis.

         What was it?

         Based on this experiment, were the microglia engulfing apoptotic cells, or      otherwise viable cells?

    

QUESTION 6

  1. The presence of DAPI in      a phagoyctic cup is taken to mean that:

  

the microglia are   engulfing debris

 

the microglia are   engulfing cells (DAPI stains the nucleus, specifically DNA)

 

the microglia are   undergoing apoptosis

 

the microglia are   impermeable

10 points   

QUESTION 7

  1. The phagocytic activity      of microglia could be intrinsic to the sex (XX vs XY chromosomes). How do      the authors investigate this? What result do they find?

    

10 points   

QUESTION 8

  1. What question did the      authors attempt to address using the thymidine analog      5-bromo-2-deoxyuridine (BrdU)? What was the finding?

  

10 points   

QUESTION 9

  1. What molecule did the      authors use to prevent phagocytosis? What question were they addressing?      What was the outcome of this experiment?

     

  

10 points   

QUESTION 10

  1. What are some putative      or known roles of the anterodorsal (MeAD), anteroventral (MeAV),      posterodorsal (MePD), and posteroventral (MePV) regions of the amygdala      (this may not be in the paper)?