haematology: bone marrow Flashcards
What is the suffix for increased in blood cell count
-cytosis or -phillia
What is the suffix for decreased in blood cell count
-cytopenia
What is apoptosis
Programmed cell death that is a normal physiological process where old, damaged or unneeded cells are removed from the system
Where do you find bone marrow
Central cavities of axial & long bones
What is 3 differences between compact & spongy bone
Compact bone:
Dense outer layer
Parallel osteons
Blood vessels
Spongy bone:
Head of long bones
Trabecular with no osteons but osteoblasts,-clast & -cytes
No blood vessels with red & yellow bone marrow
What is the two types of bone marrow & functions
- Red bone marrow: supplies nutrients to cells in trabeculae & site of haematopoeisis
- Yellow bone marrow: stores fat & changes with age (extreme cases can reactivate)
Histology: name the big arrow, arrowhead & long thin arrow
image
What does newborns bone marrow consists of mostly
Cellular bone marrow
What is aplastic anaemia
Body stops producing enough new blood cells
What is the cause of aplastic anaemia
Result of bone marrow damage happening at birth or after exposure of radiation & chemotherapy
What is six components of the microenvironment in the bone marrow
Osteoblasts: forming bones
Endothelial cells: line blood vessels & passage of cells to bloodstream
Stromal cells: produce ECM
Cytokines: cell-signaling
Adhesion molecules: binds cell to each other & within the matrix
Macrophages: clean up cellular debris
What is the two main functions of bone marrow
- Haematopoiesis
- Immune system
Where is the site of hematopoiesis at different ages
Embryo: yolk sac until 6-12 weeks
Fetus: liver & spleen until 2nd trimester
Fetus & adult: bone marrow
When & where does extramedullary hematopoiesis occur
Certain disease states
Liver & spleen
What is the three immune function of bone marrow
- Production of leukocytes
- Interaction between leukocytes
- Production of cytokines & antibodies
What is cell differentiation
Process where immature, undifferentiated cells become more specialise in appearance & function
What is the process of cell differentiation
Some HSC become quiescence cells while other undergo asymmetrical division. Some cells undergo self-renewal while other undergo differentiation into progenitors cells & become mature cells
What is quiescence cells
Less vulnerable to harmful insults & in periods of need then exit quiescence cell state
What is self renewing cells
Some of daughter cell enter cell cycle to divide & differentiate other undergo self-renewal & remain HSC
What is cell proliferation
Cells divide continuously to form many driven by growth factor & anti-apoptotic signals
What is the three mechanisms of bone marrow pathologies
- Bone marrow infiltrations
- Bone marrow failure
- Bone marrow suppression
What is the three causes & consequences of bone marrow infiltration
- Hematological malignancies leading to cytopenia
- Non-hematological malignancies leading to cytosis
- Infections leading to cytopenia
What is a cause & consequences of bone marrow failure
Aplastic anaemia leading to cytopenia
What is a cause & consequences of bone marrow suppressions
Drugs, toxins & sepsis leading to cytopenia
