Week 2 DONE Flashcards
primary lymphoid organs
- thymus and bone marrow - where lymphocytes are initially formed
secondary lymphoid organs
- lymph nodes, the spleen, and diffuse lymphoid tissue found in the mucosa of the digestive system, including the tonsils, Peyer patches, and appendix - has a mantle and a germinal center
germinal center
- filled with large lymphoblasts undergoing immunoglobulin gene recombination, rapid proliferation, and quality control.
What are the secondary lymphoid organs
Lymph nodes, white pulp of the spleen, tonsils, BALT and GALT
What is BALT, and GALT
Found in the wall of the respiratory and digestive tracts
What are immune/lymphatic systems two main functions?
· Immune response and recognition of self/non-self.
What are the two main components of the immune-lymphatic system?
Lymphocytes and stromal/accessory cells
What are the lymph node functions?
· Filters the lymph, maintain and produce B cells, and house T cells
What is the structure of a lymph node
· Consists of a capsule, a parenchyma, lymphatic vessels and lymphatic sinuses.
What is parenchyma of a lymph node
· The cortex and medulla
What is the deep cortex/paracortex
Area of the lymph node that houses T cells
What is the hilum
· Location of the efferent lymphatic vessels, artery, and vein of the lymph node.
What is the cortex
· Area of the lymph node that contains lymphoid follicles plus helper T cells and HEVs.
What is the outer/lymphoid follicle
· Area of the cortex that is B cell rich
What is the inner cortex
Area of the cortex that contains helper T cells and HEVs
What is a HEV
Postcapillary venules with a simple cuboidal endothelium that allows 90% lymphocytes to enter the lymph node.
What is the para-cortical zone
B and T cells interactions take place here
What is a primary lymphatic follicle
Contains inactive/naïve lymphocytes and dendritic cells, is found within the lymph node’s cortex, and has no germinal centers
What is a secondary lymphatic follicle
Contains germinal centers and a mantle and marginal zones
What are the medullary cords/sinuses
Contain plasma cells which release antibodies into the lymph
What are germinal centers
· Pale staining areas where antigenic stimulation of B cells takes place
What is the paracortex
· Location where HEVs are found
What is the thymus?
· Contains a cortex and non-partitioned medulla, and no germinal centers
Thymus before birth
thymus is fully developed
Thymus before puberty
When the production of T cells in the thymus is most significant
What is involution
· Replacement by adipose tissue of the thymus and T cell production decreases
What are thymic epithelial cells
· The difference between the stroma found in the thymus vs. a lymph node
What is the endodermic 3rd pharyngeal pouch
Where thymic epithelial cells come from embryonically
What is clonal selection
What thymic cortical epithelial cells do
What is clonal deletion of potential autoreactive T cells
What thymic medullary epithelial cells do
What is the blood thymus barrier
A layer formed by squamous epithelial cells, endothelial cells, and pericytes
What is Hassell’s corpuscle
A landmark of the thymus, found in the medulla, and produces lymphopoietin
What cells stimulate single positive T cell maturation
· The function of dendritic cells in medulla
What are double-negative T cells
T cells found nearest to the subcapsule
What are double positive T cells
T cells that express TCR and co-receptors CD4/CD8, and become receptive to peptideMHC complexes.
What is positive selection
· T cells that recognize self MHC molecules (and self or foreign antigens) and survive to move to the medulla.
What is negative selection
· T cells that recognize self MHC and self antigens (on surface thymic medullary cells), and are eliminated by dendritic cells and macrophages
What is periarteriolar lymphatic sheath
· Where the T cells are found within the white pulp of the spleen
What spinal level is the hyoid found at?
at the level of the C3 vertebra in the angle between the mandible and the thyroid cartilage
laryngeal prominence
- inferior two thirds of thyroid catrilage two plate-like laminae fuse anteriorly in the median plane -also known as adams apple
Where does common carotid bifurcate?
level of the superior border of the thyroid cartilage into the internal and external carotid arteries
what forms the neck?
cervical vertebrae (posteriorly), hyoid bone (anteriorly/superiorly), manubrium of the sternum (inferiorly), and clavicles (anteriorly)
Disk between C3 and 4 related structures
bifurcation of the common carotid artery
C4 and 5 related structures
thyroid cartilage
C6 related structures
-cricoid cartilage -beginning of esophagus -beginning of trachea -vertebral artery enters transverse foramen
C7 related structures
-isthmus of thyroid gland -highest point of the thoracic duct
Fascial layers of the neck order from anterior to posterior
Investing Infrahyoid m. fascia Pretracheal Buccopharyngeal Alar fascia & carotid sheath Prevertebral Investing
what fascial layer prevents superficial skin abcess from spreading further into the neck?
Investing fascia, as well as infrahyoid and pretracheal fascia
what is this?
- trace the path of lymph
- areas
- lymph node
- afferent lymph vessel -> subcapsular sinus -> paratrabecular sinsuses -> medullary sinuses -> subcortical sinuses -> efferent lymph vessel
- cortex, paracortex, medulla
cells in different areas of the lymph node
- cortex: subcapsular sinus- APC, lymph with antigens, lymphocytes; lymphatic nodule- developing B cells
- paracortex: T-cells
- medulla: cords- T/B cells, plasma cells; sinuses- discontinuous endothelium and reticular cells
difference between a primary and secondary follicle?
- primary follicle does not have mantle and germinal center
- secondary follicle develops mantle and germinal center in response to antigen stimulation
what is…?
- germinal center?
- mantle?
- how long do they last?
- growth of activated B cell where it undergoes Ig recombination rapid proliferation and quality control
- where naive nonproliferating B cells are pushed to the side when another B cell forms germinal center
- 2-3 weeks; cells will be dispersed and secondary follicle structure is lost
What is this?
- made from?
- function?
- found?
- high endothelial venule
- cuboidal cells
- allow lymphocytes from blood into lymph node
- in paracortex of secondary lymphoid tissue
What is this?
- parts?
- what do medulary thymic epithelial cells secrete? function?
- thymus
- capsule, cortex, medulla- lymphopoeitin which stimulated thymic DC to begin maturation of positive T cell to optimize negative slection and ensure tolerance
What is this?
- white pulp
- how do antigens enter?
- how are antibodies secreted?
- spleen
- follicle like structure that contains B and T cells
- central artery and marginal sinus
- directly into the blood
Vertebrae
- cervical, thoracic, lumbar; what do they share in common?
- transverse process differences
- differences in movements
- consists of a vertebral body, a vertebral arch, pedicles, vertebral foramen, transverse processes, spinous process, articular processes (two superior and two inferior)
- cervical vertebrae have a foramen in the transverse process to allow for vertebral arteries and veins
- movement never occurs at a single segment of the column except for at C1-2; the whole vertebral column will move as a whole with small movements occurring at each level
imaging modality, orientaiton, and body part?
lateral soft-tissue neck, c-spine xray
modality, orientation and body part?
- abnormality?
- lateral x-ray of neck
- retropharyngeal abcess and cervical spondylosis
imaging modality, body part, orientaion, and window?
- contrast?
- abnormality?
CT neck, axial, soft tissue window
- yes
- none
imaging modality, body part, orientation and window?
- contrast?
- anormality?
ST neck, axial, soft tissue
- yes
- retropharyngeal abscess
imaging modality, body part, orientation and window?
- contrast?
- abnormality?
- dx?
ST neck, axial, softi tisse
- yes, iodine
- well circumscribed water-density mass deep to the left sternoclediomastoid
- left 2nd brachial cleft cyst
imaging modality, body part, orientation and window?
- contrast
ST spine, saggital, bone window
- no
imaging modality, orientation, body part, pulse sequence?
- alignment of the c-spine
- abnormal discs?
- bulging discs?
- herniation
- MRI c-spine, saggital, T2 W
- reversed cervical lordosis
- discs between C 2-6 with decreased signal intensity
- C 2-6
- C 4-5
superficial nervous innervation of neck
- name the nerves, origin and what they innervate
- greater auricular: from C2-3; sensation to external ear and skin over parotid gland, mastoid process and skin from mandible to mastoid process
- lesser occipital: C2-3; skin of scalp, posteriorsuperior to auricle
- supraclavicular: C3-C4; skin over shoulder, skin over neck
- transverse: skin covering anterior cervical region, anterolateral skin of neck and upper sternum
venous drainage of the superficial neck
- veins forming the EJV
- course to SVC
- veins forming the bracocephalic?
- posterior division of retromandibular vein and posterior auricular vein
- EJV -> subclavian -> brachiocephalic -> SVC
- subclavian and internal jugular
