nursingisinmyblood

biomedicalephemera:

Our Three (Brain) Mothers

Protecting our brain and central nervous system are the meninges, derived from the Greek term for “membrane”. You may have heard of meningitis - this is when the innermost layer of the meninges swells, often due to infection, and can cause nerve or brain damage, and sometimes death.

There are three meningeal layers: the dura mater, arachnoid mater, and pia mater. In Latin, “mater” means “mother”. The term comes from the enveloping nature of these membranes, but we later learned how apt it was, because of how protective and essential the meningeal layers are.

——————————————————-

  • The dura mater is the outermost and toughest membrane. Its name means “tough mother”.

The dura is most important for keeping cerebrospinal fluid where it belongs, and for allowing the safe transport of blood to and from the brain. This layer is also water-tight - if it weren’t, our cerebrospinal fluid (CSF) would leak out, and our central nervous system would have no cushion! Its leathery qualities mean that even when the skull is broken, more often than not, the dura (and the brain it encases) is not punctured.

  • The arachnoid mater is the middle membrane. Its name means "spider-like mother", because of its web-like nature.

The arachnoid is attached directly to the deep side of the dura, and has small protrusions into the sinuses within the dura, which allows for CSF to return to the bloodstream and not become stagnant. It also has very fine, web-like projections downward, which attach to the pia mater. However, it doesn’t contact the pia mater in the same way as the dura: the CSF flows between the two meningeal layers, in the subarachnoid space. The major superficial blood vessels are on top of the arachnoid, and below the dura.

  • Pia mater is the innermost membrane, which follows the folds (sulci) of the brain and spinal cord most closely. Its name means “tender mother”.

The pia is what makes sure the CSF stays between the meninges, and doesn’t just get absorbed into the brain or spinal cord. It also allows for new CSF from the ventricles to be shunted into the subarachnoid space, and provides pathways for blood vessels to nourish the brain. While the pia mater is very thin, it is water-tight, just like the dura mater. The pia is also the primary blood-brain barrier, making sure that no plasma proteins or organic molecules penetrate into the CSF. 

Because of this barrier, medications which need to reach the brain or meninges must be administered directly into the CSF.

Images:
Anatomy: Practical and Surgical. Henry Gray, 1909.

medicalstate
medicalstate:

Segmental Anatomy of the Liver.
The liver is divided into 8 segments. These are delineated by the 3 hepatic veins, dividing the liver vertically into 4, and then through the horizontal plane for superior and inferior portions.
Posterior (caudal) segment [I]
Lateral segment (lateral superior area) [II]
Left anterior lateral segment (lateral inferior area [III]
Medial segment (medial superior area) [IVa]
Medial segment (medial inferior area) [IVb]
Anterior medial segment (anterior inferior area) [V]
Right anterior lateral segment (posterior inferior area) [VI]
Posterior lateral segment (posterior superior area) [VII]
Posterior medial segment (anterior superior area) [VIII]

medicalstate:

Segmental Anatomy of the Liver.

The liver is divided into 8 segments. These are delineated by the 3 hepatic veins, dividing the liver vertically into 4, and then through the horizontal plane for superior and inferior portions.

  • Posterior (caudal) segment [I]
  • Lateral segment (lateral superior area) [II]
  • Left anterior lateral segment (lateral inferior area [III]
  • Medial segment (medial superior area) [IVa]
  • Medial segment (medial inferior area) [IVb]
  • Anterior medial segment (anterior inferior area) [V]
  • Right anterior lateral segment (posterior inferior area) [VI]
  • Posterior lateral segment (posterior superior area) [VII]
  • Posterior medial segment (anterior superior area) [VIII]
wr-u

catsbeaversandducks:

Post-it Notes Left on the Train

Writer and illustrator October Jones, the creative genius behind Text From Dog and these funny train commute doodles, is at it again with these hilarious motivational post-it notes that he leaves on the train and in other random places.The upbeat doodles, which star Jones’ adorable character Peppy the Inspirational Cat, convey positive and funny messages meant to motivate daily commuters. Whether you’re feeling the Monday blues or in need of some encouragement, Jones’ delightful post-it notes are sure to brighten your day and remind you just how awesome you are.

Via My Modern Metropolis 

wr-u

bialogue-group:

New Documentary Highlights Discrimination Within the Black Lesbian/(and Bisexual) Community

The Same Difference is an hour-long documentary about lesbians who discriminate against other lesbians and bisexual women by Nneka Onuorah, an associate producer for BET.

“It’s almost like a gang,” Onuorah tells ELIXHER. “This is the criteria. This is what you have to do or you’re not a part of it, you’re not in it, or you’re not real. I thought that was ridiculous” … she wanted to start the conversation and shed some light on those issues …

So far, the teaser has been well received. The LGBT community wants to see it because they are living this every day…

Her fundraising goal is $15,000 and the money raised will go to production costs for her to complete the film. Onuorah does not want to only get the major city perspectives that are always seen. She wants to talk to people in states like Utah, Arkansas, and Washington … she also wants to make sure the message is heard by everyone, not just the lesbian community.

“It’s the same difference,” she says. “It’s not like we [lesbians] just face discrimination or we discriminate against each other and have stereotypes. This happens in the African American [heterosexual] community. From culture to culture, we’re doing this to each other. You can take the ‘lesbian’ out of the film and it will still be as powerful”The Same Difference is sure to spark a national dialogue around identity and the way we police one another. Give what you can to help make this important film happen. Donate here.